FOB key

FOB key Tips and Tricks

With the advent of electronics, life for many has become somewhat easier and high-tech. Case in point, the trusty television cordless infrared remote control and its earlier ultrasonic equivalents. Both circumventing the "jack in a box" activity we all so enjoyed, during the days of legacy non-remote control television sets. Likewise, our cars has also gone high-tech, flaunting electronic car key remote controls with features never seen before. No longer using infra-red or ultrasonic but a coded signal modulated in a wireless radio frequency in the 315 to 434 mhz range.  

Not only has remote controls replaced the aim push and turn function our writs won't forget but has gone far beyond locking or unlocking doors, remotely starting the car,  emitting chirping sounds with flashing hazards to assist us to find our car in a fully populated parking lot. These fancy electronic remotes control marvels are referred to as a "fob", an acronym for Frequency Operated Button. In a previous lifetime, a "fob" was the name given to the chain connecting a packet watch to its owner. Today the "fob" is form of invisible tether, chaining the remote to the car. Some say the word "fob" comes from the German word Fuppe, meaning pocket. I suppose that's where its going live when its not on the car. 

Manufacturers are constantly adding more features to the already multitude of functions that make both the car and the key "fob"  more useful than ever before. But its not all done in the name of the client. It has allowed manufacturers skimp of a few items that drove the price of the car up ever so slightly. Fobs allowed them to only install a single driver-door key cylinder, thereby saving on the cost of the other three, the installation time and somewhat reduced the weight of the car, alongside so many other items.  Collectively contributing to its overall fuel economy. But the quality of this driver's door cylinder isn't design nor manufactured robust enough and daily use. It's intended for emergencies only use, when the key is either locked inside the car or the battery had died of the "fob"  has gone faulty. Using it daily will kill that lock before you can fluently say, Rumplestillhurrywisepunywalgeemuckagee.

VW button mechanically operated switch blade "fob" comes in 2 basic flavours -- 2 button and 3 button.  One buttons specifically  for lock and the other for unlock. Keeping the button depress for a few seconds activates windows either open or close whichever is needed.  A flashing LED on the remote denotes communication.
Depending on the ECU/ control module settings, button depresses can be either audible or visible or both. Meaning a peep or two from the hooter and single or double flashing of the hazard light, or nothing based on personal preferences.  In the case of a 3 button, much like the 2 it just has a 3 for trunk release. In those vehicles with an auto lift trunk piston feature, pressing the unlock button will is open the trunk completely. 

The "fob" is a sophisticated piece of equipment but when it misbehaves, and you have to make multiple attempts before it performs a function, it could be that the battery is going flat. This is easily verified by viewing the intensity of the blinking LED on the "fob". A faint LED is a tell tail sign the the battery is giving up the ghost. When the battery is replaced, the "fob" needs to be reset. This can be done by pressing the lock one second while the car is locked. Nothing will happen except perhaps a low volume yet mechanical clunk. Remove the cylinder cover, unlock and re-lock your your car with the master-key, not spare key. This action will cause your "fob" to reset itself.

When the car wont start and the light is flashing the key, keep it close to start button to make reading the key easier so that the car will start. VW Tiquan and some other later VW's allows  "fob"  synchronization and reprogramming of driver preference like, radio stations, mirror positions, etc.  Since a detailed rundown of the procedures are beyond the scope of this post, your owners' manual is by far your best bet. 

VW Fuses Switches and Relays

VW Fuses  Switches and Relays

Single Pole Single Throw

Electrical switches comes in several configurations, but are normally classified into only four types. The most common switch is the single pole single throw, abbreviated as SPST. This implies it has one contact that is normally open —abbreviated N/O—  which is closed when the switch is flicked. This type of switch is either on-or-off / open circuit or closed circuit. This switch also comes in the form of a push button switch which is normally open and closes when pushed but when released it open once again. It is also known as push-to-make, abbreviated PTM. An example of a PTM is a door bell switch or a cars hooter or the individual keys on a keyboard. Push button switches also comes in a normally closed configuration and opens when pushed, but when released, it closes again. Commonly  known as push-to-break, abbreviated PTB. An example of a PTB switch is used to release a door, held closed by an electromagnet.

Suzuki GS500 GSXR1100, Honda  VT 500 VT600 VT700 VF750,
Kawasaki ZX1000 ZX 1100 Solenoid

Single Pole Double Throw

The second and slightly more advanced switch is the single pole double throw switch, abbreviated as SPDT. This is a three terminal switch which toggles between two states when switched. SPDT are in essence two switches in one package. The one switch is normally open whilst the other is normally closed. By flicking the switch the two switches reverses their roles. The normally open switch is then closed and the normally close switch is opened. By connecting a SPDT at either end of a long passage to turns the lights or off, one is able to enter the passage at one end, turn the lights on and when exiting the passage at the other end switch the lights off. SPDT can be used as a SPST in an application by just using the centre contact and either one of the other two contacts, depending on what type of switch you need, N/O or N/C.  SPDT switches are also available with a centre-off position, known as momentary (ON)-OFF-(ON) switch.

Volkswagen 4H0951253 Starter Relay 645 and 1J0906381A Fuel pump relay 109. 

Double Pole Single Trow

The third type of switch is the DPST and is similar to the SPST switch in operation except that it has a pair of on-off switches that switch together. It is commonly used to connect / interrupt both the live and neutral supplies in a circuit simultaneously or it may be used to switch two separate circuits simultaneously. Computer power supplies have DPDT switches as a safety feature to avoid getting electrocuted whilst working on the power supply if only one pole was switched. 

Double Pole Double Throw

The fourth type of switch is the DPDT and is similar to the SPDT switch in operation except that it has a pair of on-on switches that switch together. It is commonly wired to reverse the direction of a DC motor or be used to switch between to different colour LEDS. DPDT can be used as a DPSP in an application by using the centre contact and either one of the other two contacts and duplicated on the paired switch. DPDP switches are also available with a centre-off position, known as momentary (ON)-OFF-(ON) switch.

Switches 

Switches switches come in various shapes among which are Toggle switches, limit switches, reed switches, micro switches, mercury switches, rotary switch, slide switch, rocker switch, pneumatic limit switches, selector switches and getting the right switch for the job cam sometimes be tricky and may be better suited by using a relay. Many switches also come with a rubber jacket to make it  waterproof. However that doesn't imply you can submerse the switch in water, it is more a splash proof cover than a water proof one. There are switches suited for using under water, for example a floating mercury switch. when a vat or tank is filled with liquid, the switch would float in the upright position but when the liquid falls below a certain lever  the switch would float upside down and trigger. Perhaps turning on a pump that would fill the tank or vat once again.

Whats a relay?

Having discussed switches you may ask what does switches have to do with relays. The simple answer is, a relay is essentially a remotely controlled switch. Relays are controlled electrically rather than mechanically, hence they're known as electro-mechanical relays. They are commonly used in automotive design, where high current devices can be switched from a cockpit fairly cheaply. In stead of using long lengths of thick high current cable and a substantially heavy duty on-off switch to control a heater or a motor situated some distance from the driver; a small low current switch and a length of thin low current cable and a relay switch with heavy contacts would suffice. Every relays has a solenoid configured as an electromagnet. So when the solenoid is activated by a trigger voltage, the electromagnet pulls a set of heavy duty contacts to make or break a circuit. Relays are versatile and can function as a simple spst switch, or a more advance spdt switch of a dpst switch or a dpdt switch depending on the circuity it needs to control.

Volkswagen Solenoids

Sometimes you may need a switch with more contacts than the best switch you can find, and this is where relays outweigh switches. Relays also cost less than the combines cost of all the switches that it replaces or that can do the job of.  Volkswagen have several relays throughout its electrical system and the most hardworking relay, is the starter relay.  Starter relays form part of the starter, the reasoning, is to keep high current conductors as short as possible. However many cars have a second relay inserted into the fuse panel that powers the starter solenoid. So when you turn the ignition key to start your car, the starter relay contacts in the fuse box sends 12V to the starter solenoid on the starter. This solenoid's contacts throw and sends 12V from the thick battery cable that's connected to one side of the starter solenoid directly to the starter's field coils, causing its armature  to spin. But at exactly the same time the solenoid performs a dual function as it kicks the bendix forward into the ring gear's teeth.  The starter's force of rotation is sufficient to crack the engine and if all's well, the engine with start. 

Volkswagen

Volkswagen

Volkswagen cars are extremely popular. In fact, they are so  popular that Volkswagen as a brand is the favourite car of many South Africans, besides being the most popular car sold on the South African market. Volkswagen cars are also popular elsewhere and are sold in virtually every country throughout the world; but its popularity and its global acclaimed robustness doesn't make it indestructible. 

Volkswagen cars give problems, in fact they are more troublesome now, than they've ever been. The reason, the ODB-II system with its ever increasing number of ECUs.  This system has several features that means well, like controlling toxic emissions, like giving you the best fuel efficiency;  and is capable of detecting minor issues or glitches before they actually occur, among so many other beneficial features.

However, like every coin has two sides, and as there are always two side to every story, there is also a reaction to every action.   Meaning for every beneficial feature of OBD-II there is a detrimental feature to OBD-II. OBD-II is essentially a computer system with a host of additional computer modules remotely placed through the body of the car, some of which have an effect on the Engine ECU. 

These modules or sub-ECUs oversee various features, like an airbag controller module/ECU that supervises the airbag. This module is connected to crash sensors placed in strategic positions in the car, that triggers when a crash occurs and ensure that the airbag is inflated within the required time frame. Then there is also an immobilizer module/ECU that supervises the starting process ensuring the correct code from the key transponder chip corresponds with its randomly generated code. There is also an ABS Brakes module, a Gateway module, a Steering Assist module, an Instrument Module, a Central Convenience module, a Radio module, to mention but a few. All of which are potentially sources of problems.

If we only look at the Airbag and the Immobilizer modules/ECUs, both will impede driveability and the starting of the car, by influencing the Engine ECU. If the Engine ECU doesn't received the expected signal from either, it would refuse to start the engine. The Engine ECU is the heart of the ODD-II and normally sits in the engine compartment or inside the car under the dashboard. All three these modules/ECUs mentioned, sometimes also referred to as nodes, are in within a meter of on another but here's the downside. 

To get them to sing in harmony they are connected together by a wiring harness. This wiring harness plugs into each and every node in the car, and also share a common twisted-pair wire-connection  called a bus which is terminate at each of its ends with 120 Ω resistors. This bus can be either Controller Area Network (CAN) or  Local Interconnect Network (LIN) or even FlexRay. Each module also has a power supply and an earth connection. All of these wire connections are potentially sources of problems.

The average car can have anything between 5 and 100 modules/ECUs, some ECUs have as few as six connections and others as many as 80 or 94 or even more. Each of these physical connections are prone to corrosion, metal fatigue and physical flexing due to suspension vibration and is a source of future problems. Some ECU's earth connection is solely made through body contact and if it looses contact due to vibration or water ingress, it will undoubtedly cause an error or errors. 

These errors are stored in the ECU's non-volatile memory which can at times be quite cryptic. I can say that without doubt that every "automotive technician" has misinterpreted DTCs and replaced unnecessary components in the process. Even returned cars to the owners claiming that they solved the problem but didn't, they were just under the misapprehension that they did.

If any connection out of this glut of connections becomes intermittent for some reason or the other, it would be like trying to find a needle in a haystack and there are so many "automotive technician" that have never touched a needle nor even seen a haystack, let alone find a needle in a haystack. Be that as it may, one of the advantages of OBD-II is that it increases the likelihood of a DIY fix, providing the fixer is fairly dexterous and have some electronic and mechanical knowledge and have access to a diagnostic scanner.

A fairly common plug connection that goes intermittent, is the one that connects to the throttle body. It supplies the voltage to the stepper motor that controls the throttle butterfly valve. This plug also sends feedback to the ECU so that it knows how wide open or close the valve is. So many mechanics insist on stripping the throttle body due to a throttle body DTC and claim after cleaning it, the problem was solved. However a few days later the error would be back. A word of caution, Don't suspect replaceable parts especially if it has less that 100 000 km on its clock. Exhaust the possibility that it's a possible wiring harness problem before replacing expensive items because they can never be returned to the agents after its been installed.

Another intermittent connection it the 6 pin plug that interfaces with the accelerator pedal. This is a common source of the dreaded EPC problem. In many cases, a squirt of electro cleaner may solve this problem. That's to say until it's triggered by something else. It's worth while to check the voltage supply stability and ground impedance between the 6 pin plug and the ECU. Remembering that the pedal's earth connection is grounded inside the ECU and the ECU is grounded to the body or chassis and not the engine. In some cases, the ECU will function normally because its metal casing is not earthed.

Also, don't be tempted to earth the pedal earth directly to the body when there is a  significant resistance reading. Rather replace that portion of the wiring harness that may have gone high resistive. Offset ground connections and ground loops can cause voltage drops and magnetic impedance which are major causes of noise hum, and interference in computer systems (ECU). So don't alter the the existing ground connections because it could introduce issues you've never experienced before.

My EPC light came on

My epc light came on

Virtually every  motoring enthusiasts who owns a Volkswagen Golf TDI  simply loves its torque; its drive, its racy performance, its braking, its fuel economy and especially its manual transmission model. Be that as it may, 6 out of 10 Volkswagen and Audi owners are unhappy about Volkswagen as a whole. Unhappy about their cheating devices, unhappy about the emission scandal, unhappy about the entire VW TDI buy back claims processes, but more specifically unhappy about having to give back the car that they love so much.

According to the 225-page court document that outlines VW’s settlement, which reads,

“At the present time, there are no practical engineering solutions that would, without negative impact to vehicle functions and unacceptable delay, bring the 2.0 Liter Subject Vehicles into compliance with the exhaust emission standards.” 

This is so wrong on so many different levels hence most VW and Audi owners are completely pissed-off -pissed-off at Volkswagen. Event hough most VW TDI enthusiasts haven't returned their cars, they are already missing them, even before it's taken back; all of them very unhappy about it. It's always good to be optimistic about the buyback outcome but pessimistically speaking, VW, Audi, Seat and Skoda owner's are all complaining about their cars, ranging from, 

"My epc light came on and I lost power",  to 

"I got stranded on the side of the highway today for  almost an hour when my EPC light went on",  to 

"The first time it happened, the EPC light turned on and loss of  power lasted for a day and then it went away on it's own",  This is now the third time this happened, the EPC light comes on and then my car just loses power", 

"I took my car to the VW agents for a EPC problem who then said they  found a few error code but they didn't know what was wrong, so they just reset them",  

"Totally disgusted, by the dealer's complete and utter  disregard to accept responsibility for their pathetic  workmanship. They threw a dozen parts at the problem at my cost and the EPC problem is still not solved", 

I've kept track of all the faults on my VW Polo, and it fills a foolscap page.  It ranges  from interior parts falling off, the foot rest lodging itself under the brake pedal whilst driving, the brakes randomly engaging and causing under steer, to continual  creaks from the suspension, the gearbox is crap, not to mention my daily battle with an EPC issue. My Polo's been back to VW a full 58 days during this  year, yet they still haven't fixed all the issues and  as a result I very nearly caused 2 accidents due to  the on-going braking issue, and the EPC going  into limp mode on an on-ramp,  

I've spent more than a  year trying to solve  the problem “EPC” light problem, I've already  replaced  the Acceleration pedal, Two sensors located  under the engine, Cambelt kit, Throttle Body, all the  injectors and the ignition coils and the ECU,   but the light still regularly comes on,  

The VW guaranteed future Value a Rip-Off! I have never  been so dissatisfied with help from customer service and  will NEVER EVER purchase another Volkswagen nor recommend it to anyone I know, because of the shoddy  way we were treated. The staff working in VW credit and financial are rude and disorganized, no wonder they losing all their customers.They charged me for items covered by the warranty.

And the list goes on. These are only a few of the nice clients  I wouldn't want to repeat what some of the other "not so nice" clients said about Volkswagen and their cars, especially about the EPC light and limp mode. Electronic power Control (EPC) has become part of every VW, Audi, Skoda and Seat owners vocabulary, yet few understand what it really is. So allow me to put you in the picture.

Electronic Power Control

The EPC warning light is just a regular warning indicator light, much like your handbrake light or your oil indicator light.  The handbrake light just tells you that the hand break is engaged, alternatively that it hasn't been released. Likewise the oil light is a warning indicator that alerts the driver to the fact that the oil is low. In the very same vain the EPC warning  light is just an indication that something awry has happened in your Volkswagen's torque system, which is a sub-circuit of the Electronic Power Control Circuit.  

So what exactly is the torque system ? you may ask. Well is consists of various interlinked components, where the functionality of one is subject to another. These components are your  Volkswagen's entire drive-by-wire system, incorporating the  accelerator pedal, the throttle body, the cruise control, the traction control, the breaking system, the fuel pressure system, the knock sensors and the ECU, along with the wiring harnesses that inter-connects all these components. The wiring harness is a safer substitute for accellerator cable in all drive-by-wire systems.  

The accelerator pedal

The accelerator pedal for that matter, has 2 independent potentiometers inside a module that's permanently bonded to the pedal itself. These 2 potentiometers are call senders by Volkswagen and known as G79 and G185, but I will use these terms interchangeably.  This module is connected to the ECU via a 6 wire harness, essentially 3 wires per senders. Before, I continue, let me tell you what a potentiometer is, if you not familiar with the term. Another name for a potentiometer is variable resistor or a rheostat. It is most commonly used as rotary the control knob on a radio, with which to control the level of its volume. It is also commonly used in  the bedroom light dimmer to adjust the level of light needed. 

Each sender has 3 pins, 1 for each end of its resistor and 1 pin for its wiper. All three pins of each sender are connected to 3 pins specific pins of the ECU. The ECU sends each sender a high and a low voltage across their resistors and receives a difference fed back voltage from each sender's wiper. The 2 wiper feedback voltages are referenced and inverted to one another and translated by the ECU as how much the accelerator pedal is depressed.  Should  the ECU loose either of the wiper inputs for even a fraction of a second, the ECU limp mode program will execute, the EPC light will come on and the engine wont rev higher that 2000 rpm any longer. When my EPC light came on, I traced it back to a fault/ intermittent accelerator pedal due to error codes P1630  to P1634 and P1639.

The throttle body

Much like the accelerator module, the throttle body also has 2 integrated potentiometers called angle sensors known as G186 and G187. They inform the ECU how wide open or closed its butterfly is. The throttle body also has a built-in stepper motor known as an actuator. The ECU essentially translates the accelerator pedal position to a voltage / pulse train that drives the stepper motor, that in turn opens and closes the throttle body butterfly, controlling  air flow between air filter and intake manifold.  In a nutshell, a remote control system that mimics the operation of an accelerator cable. If for any reason the throttle body is removed or dismantled, it would be necessary to perform the adaptation procedure. When my EPC light came on, I traced it back to a  throttle body problem with error codes P1171 - Angle Sensor 2 for Throttle Actuator (G188) Implausible Signal.

The cruise control

When the cruise control is enabled, a signal is sent to the ECU to this effect, which in turn sends the necessary voltage / pulse train to the throttle body stepper motor to keep it steady and received feedback from G186 and G187 to further control the process., ignoring the accelerator pedal until the brake is applied or receiving a signal change from the accelerator pedal. Should something go awry in this process, cruise control will be canceled, the ECU limp mode program will execute, the EPC light will come on and the engine wont rev higher that 2000 rpm any longer. When my EPC light came on, I traced it back to a  cruise control switch problem with error codes  00895 - Cruise Control Switch (E45) Defective.

Volkswagen Ignition System

Did you know that the electronics industry has had the fastest growth in the shortest amount time, compared to all other industries worldwide? But  before I expound on that, let me just say that, the invention of numerous mechanical contraptions during the late 1800s, like James Watt's steam engine for example, started the transition towards new manufacturing processes which collectively gave rise to the industrial revolution. Much later Samuel Finley Breese Morse invented the single-wire electric telegraph system and developed the Morse Code. And sometime thereafter Alexander Graham Bell invented the first practical telephone system and their collective efforts, without discounting anyone else's efforts, changed telecommunications forever. 

Added to this, ancient records show that the first streets of Baghdad were paved with tar, and that the Babylonians used asphalt to construct the walls and towers of Babylon. Even The I Ching bears testimony to the fact that the cites of China used oil extracted in its raw state before refining was first discovered, during the first century BCE. By implication, tar, crude oil and pitch, were used as a sources of fuel for a very long time before paraffin was distilled from it. When this finally happened, the thin distilled paraffin was commonly used as fuel for lamps whereas the thicker residue was used to lubricate machinery. Soon after or in and around this time, when oil/fuel was extracted from coal, Étienne Lenoir successfully innovated the internal combustion engine followed by Nikolaus Otto who became famous for successfully developing the compressed charge internal combustion engine - the Otto engine. 

Now Henry Ford on the other hand wasn't an inventor nor an innovator, by any stretch of the imagination, as many are led to believe. He was rather a  business magnate and a captain of industry, who formed the Ford Motor Company, and sponsored the development of the "assembly line technique" for vehicle mass production. One could clearly say that their collectively efforts, without diminishing any other contributor's efforts by the very least, over a period of some 200 years, are partially responsible for the social changes and economic development that shaped societies that we live in today. 

Electronics

However, when the mechanical inventions of the Industrial revolution, is compared to modern day electronics, it stands out like a global coup. Initially there was the vacuum tube aka the electron tube, colloquially known as a valve. It gave way to semi-conductor devices as a whole. Transistors and gave rise to the analogue Integrated Circuits (IC) aka chip, followed by Transistor/Transistor logic TTL chips, followed by  digital semiconductors like complimentary metal oxide  semiconductors (CMOS) chips, ROM (digital read only memeory), RAM (random access memory) chips, EEPROM (electronically erasable programmable read only memory) chips. 

This was followed up by large scale integration (LSI) chips and Very Large Scale Integration Chips (VSLI ) chips. With the advent of multi-layer circuit boards and surface mounted technology, microcontroller (system on a chip) SoC and  microprocessors (µP) became pervasive. Assembler language for chip families was developed and compiled to high level languages for programmable chips while software programming sat at the heart of most electronic devices and electronic systems. Communication protocols were developed and networks of various types became mainstream. All of this happened in 50 years as opposed to 200 years as mentioned above.

Volkswagen Ignition System

So you may ask, what has all this history to do with Volkswagen, Audi, Seat and Skoda and for that matter all vehicles from plains to trains? Well the short answer, everything! Much like the industrial revolution with its mechanical enginuity;  cars and planes were also predominantly mechanical since its inception, its mechanical Ignition System was prone to imprecise ignition timing, resulting in improper fuel mixture burn, thus increasing its exhaust pollution. With the rise of telecommunications of old, so did the electric wires, and electrically controlled gauges, and relays switches in cars and planes multiply.

The ever inflating cost of gasoline then triggered the invention of CDI (Capacitive Discharge Ignition Systems) which is in fact the first type of electronic contraption integrated into the Ignition System of a vehicle in order to, more precisely control its ignition timing making it more fuel efficient. These devices were available as add on kits and not produced as standard equipment in cars at the time. The preferred standard equipment was the IDI  (Inductive Ignition System) and is the most common Ignition System found on all cars built prior to 1980. It used a coil, distributor incorporating breaker points in its Ignition System that was prone to ware-out due to arcing on contact.

During the 80's engines still used a coil and a distributor but was computer controlled, and by the 90's the computer evolved to an ECU, replacing the coil with a power pack. However, with the constant and ever increasing price of gasoline and looming environmental concerns about vehicle exhaust pollution; the automotive industry then accelerated its R & D into newer and denser, more fuel efficient engines and power-train systems capable of higher power output with enhanced robustness. 

With the demand for higher-km/litre vehicles, Auto Ignition System needed to undergo an extreme revolution to produce a more  advanced Ignition Systems. So, by the 90's an Insulated-Gate Bipolar Transistor (IGBT) was introduced into the Ignition System as a discrete component connected to the ECU. It essentially replaced the bi-polar transistor used in older systems. 

Insulated-Gate Bipolar Transistor 

An Insulated-Gate Bipolar Transistor (IGBT) is a fancy transistor, a semiconductor that functions like a switch.  Unlike mechanical points, a semiconductor switch doesn't have moving contacts and is thus referred to as a solid state switch capable of handling Voltages between 600 Volts and 3300 Volts. So in a nutshell and IGBT is a fast solid state switch capable of switching speeds between 6 ns and 125 that and can be remotely controlled.  It is thus controlled by the ECU via a driver module. The 12V DC traverses the coils winding and its negative side is connected to the collector of the IGBT which switches it to earth giving rise to induction in its secondary winding that produces the spark. Switching on and off also creates heat in the collector/ emmiter junction, cable of withstanding maximum junction temperatures of 150°C and 175°C. So as can be seen, an IGBT its just a fancy transistor, it is the latest technology needed for engines to operate at higher compression ratios that need higher spark plug voltage that can emit greater energy to ignite lean air and-fuel mixtures.

Post Y2K  technology

Starting from Y2K Ignition Systems were all ECU based, but the power packs of the 90's were replaced by dedicated coils per engine cylinder,  yet making use of an Insulated-Gate Bipolar Transistor (IGBT) as discrete component but connected to the ECU. From 2004 to 2010 the discrete Insulated-Gate Bipolar Transistor (IGBT) integrated into individual Ignition Coils evolved to the all new Smart IGBT connected to the ECU. In later technologies the discrete / Smart IGBT evolve into a IGBT Module also integrated into each of the individual coils. 

What this implies, is that each spark plug have its very own coil completely independently switched by a Smart IGBT module driven by the ECU to an extremely tight tolerance. The ultimate objective is, that the ECU, whilst maintaining absolute  stoichiometricity,  triggers the Smart IGBT module that in turn fires the spark plug at the precise moment to attain  absolute combustion.

The accurateness of the entire ignition timing process is  determined by the ECU. Its internal programming tightly controls  ignition timing process yet subject to inputs from several engine sensors as well as engine speed, torque and  temperature. Should the spark occur too early, the resulting combustion chamber pressure, then applies force to the crankshaft before its force can be transformed into continued rotation. This could cause pre-ignition. Should the spark occur too late, the combustion chamber pressure peak weakens rapidly as the chamber volume rapidly increases as the piston moves downwards. This normally results in  incomplete combustion, causing possible  knocking.  Both pre-ignition and knocking are totally undesirable and the most common cause of hydrocarbons - unburnt fuel exhaust white smoke. This unburnt fuel igniting in either the intake manifold or the exhaust system would result in back-firing.

Ignition Error Codes

Any such undesirables would trigger a DTC error codes in the P0300 range. P301 misfire cylinder 1, P302 misfire cylinder 2, P303 misfire cylinder 3, P0304 misfire cylinder 4. This can be extrapolated up to P0312 for a 12 cylinder engine. In the same vane, every component involved in delivery of a spark to the relevant combustion chamber can cause misfires. The coil can present a misfire, the spark plug can cause a misfire, the  wiring  between the ECU and the coil can cause a misfire, the Smart IGBT module can cause a misfire, the IGBT driver can cause a misfire and even the IGBT itself can cause a misfire.

Volkswagen_Polo

Volkswagen_Polo

During the winter of 2018, the Western Cape hasn't received a similar volume of rainfall as it did in previous years, thus draining its reservoirs to its last 10%. So, due to water scarcity a drought alert  was raised, along with the price of water. Water restrictions were implemented, water was denied, rain water was caught in Jojo tanks by many. Grey water became a buzz word and people lined up at the aquifers to collect drinking water.  In a nutshell we had a water crises and much like the price of water, the price of fuel in South Africa is also staggering.

Staggering isn't perhaps the most appropriate word  to use in this case because in essence, staggering  implies stumbling, almost falling rather than constantly rising. So I'm going to resort to words like astonishing, outrageous even scandalous. Yet this hasn't impeded car sales in the very least because cars are being sold in huge numbers monthly, despite the economic situation in SA. Not to mention that President Zuma was impeached and removed from office causing both Moody's and S&P to downgrade South Africa's foreign and local currency to junk status. Then there is also South Africa's unemployment rate that borders on 27%, followed by its  crime statistics that has somewhat decreased by 1.8% comparative to 2015/16, inclusive of vehicle theft.

Meanwhile the VW Polo reigns supreme, as the most popular and best-selling passenger  car in South Africa, closely followed in second place by its cousin,  the Polo Vivo.  The Toyota Corolla, Auris and Quest sales comes in third place, closely followed by its cousin the Etios that took sixth place.  Then there is the Kia Picanto followed by the Renault Kwid followed by the Hyundai Creta. 

The importance of this observation is that all these cars are smaller  than the average medium sized family car. The expectancy is that being smaller, they would also be more fuel efficient but that's certainly not the case. It turns out that the Ford Fiesta 1.5 TDCi Trend, the the Fiat Tipo 1.3 Multijet Easy, Fiat 500, the Peugeot 2008 1.6 HDi Active and the Fiat Panda 0.9 TwinAir Easy are the most fuel efficient smaller cars on the road respectively. But their fuel efficiency is liked to impeded functionality, cramped seating with hardly any boot space.

Why Buy VW Polo

People buy VW Polo's for its sophisticated look and feel, its overall build quality and its youthful appeal, its comfortable seating and its lavish boot space. Polo also delivers superior performance and is more pleasing to drive. They are affordable both new and second-hand and cheap to insure. The Volkswagen Polo brand has been around since 1975 and is now in its seventh generation and is also sold as the Skoda Fabia and the SEAT Ibiza. 

It just makes economic sense to drive and own a VW Polo because its spare parts both used and new are in abundance. The Polo TDI BlueMotion takes fuel efficiency to a new level and is one of the most fuel-efficient non-hybrid cars in SA, employing the same 1,0-litre turbo triple as the Audi A1. Beside VW offers a three-year, 60,000-mile warranty as standard on every Polo. Though not as fuel efficient as the match-box Fiats mentioned above.

So, considering the ever rising price of fuel, its just a matter of time before every household would want to store some in Jojo tanks underground to get a reprieve from paying  these outrageous and scandalous fuel prices. If you want a fuel price alert when it increased .... and possible decreases, click here!

What is Limp Mode

What is Limp Mode

Limp mode is a safety feature specifically designed into the OBDII system to protect the engine and or transmission from damage. In the event of a engine malfunction or in response to the "warning" lights,  the driver would be provided with advanced warning giving him or her sufficient time to get the car off the road. 

This safety feature is triggered when an abnormality is detected with the logic circuitry by the vehicle's computer, viz  Engine Control Unit (ECU) aka Electronic Cobtrol Module (ECM) or even the Transmission Control Module (TCM). Theoretically these modules receive constant signals from the MAF, MAP, TPS, vehicle speed sensor, cam position sensors, engine sensor and so many other sensors. As long as these signals that stay within the “normal” range of predetermined signal levels, all's well. Since operating conditions do change as the vehicle is driven, these signals will somewhat change and may occasionally exceed or drop below the pre-programmed level.

This event alerts the ECU/ECM to the glitch and gets stored as information. This glitch condition is them monitored by the ECU/ECM for the next few driving cycles. A driving cycle is any distance traveled between the start of the engine and swtching the engine off. It this glitch occurs a few more times during sucessive driving cycles it is registered as an error code in the ECU/ECM's non volitile memory. However if the glitch doesn't reoccure during sucessive driving cycles, that glitch is deleted.

Sometimes the yellow check engine would turn on, though the car drives and performs perfectly normal. After a few cycles the yellow check engine light then turns off as if the event never occurred.  Sometimes the glitch like  a misfire occurs and could be severe enough the trigger Limp Home Mode. Limp home mode is an operating condition that is triggered by the vehicle ECU. In the case of an automatic vehicle, limp mode will limit the transmission to 2nd gear and limiting the speed to 15 to 20kms p/hour. This may cause the engine to have a higher rev than you may be accustomed to hearing. This will also cause the vehicle to be sluggish on pill away since it is limited to 2nd gear and will not change.

Once the problem / error code is diagnosed and the appropriate sensor that's causing the problem is seen to or replaced, everything should be back to normal.

Fail Safe Mode

Fail Safe Mode

"Fail Safe Mode" aka "Limp Mode"  is becoming more common as the guarantees on cars of all makes and models are starting to expire. As cars are getting older, they also tend to be affected by fail safe more frequent than ever before. In fact now a days, its quite difficult to find a car fitted with OBDII that hasn't gone into "fail safe mode" or "limp mode" at some time or the other,

"Limp mode" is normally instantly identifiable and have a number of symptoms. These symptoms range from the car's engine switching off in mid travel, the engine idling but its won't rev, the car performing sluggish on take off, or in automatic models, the transmission doesn't seem to want to shift. These are often accompanied by a flashing or permanently on check engine light or transmission light and the EPC light. When this happens to you, its best to get your car to the side of the road and out of harms way as quickly as possible. I've experience limp mode several times with my VW Polo 9N and one of them stands out as a near death experience when I just about managed to limp my car away an fast on coming pantechnicon truck, before it could hit me. 

Since VW is known to have cheated on VW vehicle test, namely the during diesel scandal, there's an idea that's been making its rounds on social media, claiming that "limp mode" was engineered by Volkswagen AG as a way of making money from all VW owners when their vehicles start to misbehave. However, this is a myth or rather it's not exactly true because "limp mode"  doesn't just affect Volkswagen manufactured cars but seems to be more prevalent on Honda,Toyota, Dodge and Chrysler vehicles with a computer controlled transmission, though not specifically.

Transmission Limp Mode

Automatic Transmission are plagued by both electrical and mechanical issues because  the  Transmission Control Module  (TCM) controls the process of shifting gear;  and because it's  located inside the rear end of the transmission itself, constantly subjected to extreme heat from the transmission oil. As such, the ribbon cable inside the becomes hard and brittle and sheds their PVC covering causing connections to short circuit or cause sensors to malfunction.

Both the Transmission Control Module (TCM) and the  Engine Control Module (ECM) depend on a stable 12 volts supply  to operate properly. So by implication, a faulty alternator can give rise to a low batteries or even dirty battery cables can cause  intermittent power issues, causing these modules not to function optimally, resulting in "Limp Mode".

When faced with a "Transmission Limp Mode" it is worth trying to perform an Adaptive learning Procedure before limping it to the service agents. This will hopefully reset the TCM and eradicate the problem. So turn on the ignition to the position where all the dashboard light are lit. But don't start the engine. Then depress the accelerator pedal all the way in, and keep it there for 1 minute and while keeping the pedal depressed turn the ignition off. Release the accelerator pedal and wait for another minute then start the car. 

Russian Autotech

Russian Autotech

Greetings fellow Volkswagen owners. I'm certain most of you will agree with me that as huge as the Internet is, it's often hard or rather difficult to find exactly what you looking for. More often than not, this pertains to information  on automobiles of every kind but especially VW, Audi, SEAT and Skoda vehicles. Be this as it may, it certainly doesn't mean that these sought after help files or information even exist; though several "mechanical services web sites" allege that they have all the answers to you motoring problems, offering said information on a paid subscription basis. In reality, there is absolutely no guarantee that they actually have the answers you need to fix your Volkswagen,  Audi,  Skoda or SEAT. The worst would be after subscribing, that this is in fact the case. 



To make matters worse, since the diesel-gate scandal, Volkswagen AG hasn't been forthcoming with information needed by the general public in order to fix or maintain their Volkswagen, Audi, SEAT and Skoda vehicles. They've been far too busy dealing with the fallout of the "diesel dupe". In the US alone, Volkswagen has already paid over €25 billion in fines and litigation costs. Regardless of this, the Dieselgate scandal doesn't look like it's going to abate anytime soon. 

Notwithstanding, this hasn't deterred Volkswagen from extending a €1.75 billion deal with Russia's GAZ group until the year 2025, to produce VW, Audi and Skoda brand vehicles at their Gorky plant in Nizhny Novgorod Oblast, despite the collapse of the Russian ruble. Meanwhile the Kaluga plant in Russia continues to produce VW Tiguan, VW Polo and Skoda Rapid models, as well as build 1.6L gasoline engines. Russia has long been touted to become the largest single car market in Europe, eclipsing Germany’s 3.35 million new vehicles registered last year though currently, many Russians can't afford to buy new cars. 

The most significant thing about this operation, is that several thousands of  Russians were empowered by VW and Audi and privy to their technology, to the point that they are willing to share it with whoever is willing to ask. So, all you peeps  who are having trouble with your VW's, Audi's, Skoda's and SEAT's and seek repair information, there are several Russian Websites that have hoards of free VW, Audi, SEAT and Skoda information that is not normally available on English / American websites. Below are a few links to Russian Websites that may have the information you are looking for. The images in this post are screen shots from these websites. Best of luck with your repairs.

The first site is  http://vwts.ru/  .... this is a Volkswagen Technical Site. All information is in Russian. Login to http://vwts.ru with your facebook account. If your Russian, like mine, extends to yes and no - "да (da) and (нет) net" respectively, then its best  to download  Google chrome's translation extension in order to make sense of the documentation. Some of the documents are in PDF format, mostly in  Russian and German but I've downloaded several written in English. This site also has a forum vwts.ru/forum/  but it appears to be insecure.

http://volkswagen-org.ru/ ... this site covers Golf 1 - Golf VI, Volkswagen Polo, VW jetta, VW Passat, VW Phaeton, VW Tiguan, VW Touran etc. It seems that its administrator has locked down new registrations, but if you manage to login, do so with the facebook icon.

https://www.vw-bus.ru .... this is a forum covering the VW combi T1 - T5, the LT, crafter, the VW Caddy and the Amarok, with members living in Russia, Belarus, Ukraine, Kazakstan, Baltic States and Europe.

https://www.drive2.ru/   ... this is a site of general interest but has good coverage of VW, Audi, Skoda and SEAT.

Check Engine Light

Check Engine Light - aka MIL

Yesterday morning when I started my VW Polo highline she idled a bit rough but I never gave it another thought because it had been raining hard throughout the night with harsh howling winds accompanied by a  lightning storm. I summized it could have been caused by the moisture in the air but when I looked at the dashboard, I saw that the orange / amber Check Engine Light was on. I tried accelerating and looked at the CEL but it stayed on. Surprisingly the engine seemed sluggish and didn't revv as per normal. Looking through the rear view mirror, I could see a distinct amount of smoke spiraling behind the car.  This was worrying because the previous day,  the car drove perfectly normal and when I parked her, she idled just fine. 

The problem with the  Check Engine light, other that being on, is that it doesn't tell you anything about the nature of the problem nor whether it's  serious or not. All I knew is that something was wrong with my emission control system because of the excessive  smoke.   The Check Engine light is actually better known as the Malfunction Indicator Lamp (MIL) so in essence there was a malfunction detected by the ECU and there was no way to tell what it could be without plugging in my scan tool. So off I went and  fetched my laptop and my VCDS cable, plugged it into the under dash DLC connector and ran a scan and found 4 Faults - P1137, P1103, P1187, and a P0441.

CODE ERRORS

17545 - Fuel Trim: Bank 1 (Add)
P1137 - 002 - System too Rich - MIL ON

Considering the first error code describes the fuel system as to rich, by implication then there is too little air for proper combustion. So I popped the bonnet to check the MAF, and saw a whole load of leaves and pine nettles strewn all over the engine compartment and a hand full of them stuck to the inlet of the air filter, blocking the air flow. I then open the air filter, removed the leaves and nettles and all those that got sucked into the air filter housing when I initially started the car.

17595 - Linear O2 Sensor; Compensation Resistor: Open Circuit
P1187 -- 35-10 - - - Intermittent

The second error directed me to the O2 sensor because the ECU describes it as  "Open Circuit".  Stooping over the engine, my eye followed the exhaust pipe, from the manifold branch past the firewall and saw a pine tree branch under the car, so I kneeled down to pulled it out but is was stuck. The tree branch was right below the  Catalytic converter.  I then went inside to fetch a garden pruning scissors so that I could cut off the protruding twigs and free the branch. Just as I was cutting I saw a wire hanging from down from the Cat. It was the wire from the O2 sensor that broke off and I supposed this happened with the force of the wind blowing the branch under my Polo.

The road and my driveway was littered with pine comes and nettles that the wind blew from the park more than a 100 meters away.  Anyway, I striped of the O2 sensor wires which was screened and reconnected them with an electrical block connector. You know the ones were you have to push the wires into a brass ferrule from either end and screw it down with the two screws. That just worked perfectly.

17511 - Oxygen (Lambda) Sensor Heating; B1 S1: Performance too Low
P1103 - 35-10 - - - Intermittent

The third error also directed me to the O2 sensor that wasn't heating up. I suppose it's linked to the disconnected wire and I assume the ECU prevented this because it realized the O2 sensor was OC. 

16825 - EVAP Emission Control Sys: Incorrect Flow
P0441 - 35-10 - - - Intermittent

The fourth error I couldn't make sense of  though I've seen this error when the fuel tank cap wasn't properly closed. So I went to the the tank, took off the cap and inspected the rubber seal. But it all seemed fine, so I closed it. I them cleared the diagnostic trouble codes (DTC) stored in the engine control module and started and re-scanned the ECU for errors and it came back with "No fault code found ". I then started my Polo and all was well. She revved as before and the Check Engine light was off.


The Check Engine light has always been a major annoyance to both motorists and mechanics,  and as a consequence is often ignored. I even know of someone  who stuck a piece of black insulation tape over the orange / amber  Check Engine light to blot it out, rather than fix the problem. Be that as it may,  ignoring the Check Engine light could lead to expensive car trouble later, so it's important to promptly address problems indicated by it.

DIY mechanics should buy and inexpensive scan tool / DTC code reader  since they are all standardized to plug into the 16 pin DLC under the dashboard. It would empower them to  discuss the problem with their mechanic if they can't manage to solve it themselves. When Check Engine light comes on, it is more likely than not that your car car is releasing unburnt gasoline (hydrocarbons) and carbon monoxide  into the atmosphere and consume a lot more fuel than it actually should.  

The OBDII system was primarily designed to monitor the emission control system continuously so it can be said hat if you car passes "readiness" its a good indication that your car  engine is in good health.  

Some problems that can illuminate the Check engine Light.

A clogged air filter can trigger the Check Engine light.
A loose gas cap can trigger the Check Engine light.
A fault O2 sensor can trigger the Check Engine light.
A Mass air flow sensor problem can trigger the Check Engine light.
Perished Spark plug wires can trigger the Check Engine light.
A blown  Catalytic converter can trigger the Check Engine light.
Low oil pressure or overheating can trigger the Check Engine light.
Sporadic engine misfiring can trigger the Check Engine light.

  

Hall Sensors

VW POLO

Volkswagen has always had an upstanding reputation (other than for the emission scandal) for manufacturing quality vehicles at affordable prices. One such car is the VW Polo hatchback which has also become one of the most popular cars in South Africa, and it’s really not hard to see why. The VW Polo is a compact car, but when driving it, it somehow feels larger, somewhat like its bigger brother - VW Golf. Should you buy one, you would certainly agree that the VW Polo has universal design appeal, that it has good performance, decent fuel economy and is sold at a relatively affordable price. 

Hall Sensor Hall Effect Sensor Switches A3144 / 3144E / OH3144E
in a TO-92UA 3 pin SIP package can be bought for as little as 1 USD

Volkswagen has capitalize on this winning formula for years and has given us plethora of Polo's to choose from ranging from the Polo Trendline, to the Polo Comfortline, to the Polo Highline, not forgetting the Polo Cross and Polo GTI which comes in 3 and 5 doors classic and hatchback versions. Engine capacities and engine technologies range from 1.2 TSI 66kW and 1.4 TDI 55 kW for the Trendline,   1.4 TDI 77 kW, 1.2 TSI 81kW for the Highline  and 1.2 TSI 81kW Highline DSG, to  1.0 TSI 70 kW BlueMotion. The sedan or VW Polo Classic comes in  1.4 & 1.6 trendline, 1.6 comfortline / tiptronic, 1.9 tdi highline (74kw)  and 2.0 highline (85kW).  There is even a GTI (Grand Touring Injection), a FSI (Fuel Stratified Injection), TSI (Turbo Stratified Injection) and a TDI (Turbocharged Direct Injection), to choose from. 

Clearly there's a Polo out there waiting for you! Having said that, owning a Volkswagen doesn't come without challenges, personally I think the biggest challenge is more likely than not the dreaded EPC light that triggers at the most inopportune times. The EPC circuit has several sensors that feeds into the ECU among them Hall sensors. From my experience hall sensors tend not to like heat, even though their specification sheets rates them above the requisite heat range.  

This datasheet gives you a good idea of a hall sensor's specifications 

Hall sensors are pervasive throughout modern day cars. Hall sensor, aka Magnetic sensors essentially converts magnetic pulses into electrical input signals for processing by electronic circuits. Magnetic sensors are solid state devices meaning there are no mechanical moving parts inside, its all electronics taking place in a sealed chip of silicon, making them immune to vibration, dust and water. This makes them popular choice by electronics designer engineers for several types of application ranging from  distance sensing, to velocity sensing, to position sensing, to  speed sensing, to directional movement sensing etc.

Hall sensors are used for angular position sensing of the crankshaft to determine the firing angle of the spark plugs. They are used for magnetic position sensing in EGR systems. They are used for wheel speed detection for the anti-lock braking system - (ABS) and speedometer. Throttle bodies with DC motors use hall sensors for position sensing. Hall sensors are also used to determine the position of the car seats and locking of seat belts. Hall sensors are employed in automatic transmissions as magnetic neutral position switch, as actuator sensors, as speed and direction sensors, for gear detection and clutch position sensing. Hall sensors are used as engine speed sensor and also as the vehicle speed sensors.  And the list goes on.

The following images depicts a hall sensor replacement inside the distributor of and Audi 5-cylinder engines 2.0 - 2.3. As can be seen the the wires have distinct colours , the red wire is +5V / 12V supply, the black wire is negative / ground and the yellow wire is the output of the hall sensor / sender.

There is space under the black plastic holder where the wires connect to the hall sensor.

Multi purpose hall sensor for automotive use, but the military spec hall sensor is a better option

The sensor is replaced, solder joints covered with fiber glass sleeving then epoxied into place.

Hall sensor plate reassembled

Hall sensor assembly fitted into distributor housing

As I mentioned in a previous blog, Hall sensors don't like heat and tend to malfunction when they get too hot. My first experience with hall sensors were when I was working as an electronics engineer for A Television and Video repair company. A video machines that employed a hall sensor in its take up clutch stopped working due to overheating.  By squirting the hall sensor with a blast of servisol rapid cooling spray, it started working again. I repeated this exercise a few times to make certain that the hall sensor was the culprit, after replacing it, the machine worked just fine. 

Then I also had a problem with my Opel Kadett 1.8 GSI  when driving in peak hour traffic. It would switched off and refused to start.  But after allowing the engine to cool, it started just fine and would be perfectly ok for days until I got stuck in bumper to bumper peak hour traffic again. The dealer had a field day with my car, telling me that they repaired a bad earth under the dash board, only to find out in peak hour traffic that they misdiagnosed. Then I was told that the loom was replaced, then I was told the ECU was replaced and finally that a hall sensor inside the distributor was replaced. This fix the problem once and for all. The images above is for the same symptoms on a Audi  2.0L 5 cylinder.  As perfect as hall sensors are for most applications, where there is excessive heat, they will misbehave.  Perhaps hall sensors mounted in heat intensive spots like the engine speed sensor, should be designed with a heatsink or have its own cooling fan. This advice is as relevant for current model cars as it was for the Audi 2.0L 5 cylinder.