The Most Common Car Problems

There was a time when car owners could easily service their own cars. Simply replacing points, plugs and condensors,  draining its oil and replacing its oil and oil filter normally put the car back on the road again. Those were the days when the most common roadside problem was a puncture or a snapped fan belt. Punctures were easily fixed with a replacement tyre from the trunk. All that was needed was some elbow grease applied to the jack, wheel brace and wheel nuts and you were on the road again. But today rollbacks are are integral part of motoring. Hundreds of cars are loaded up everyday on the road side.

The main cause of punctures was attributed to poor road surfaces, random metal objects and broken glass and to a lesser degree older tyre technology. Even though punctures were predominant, they were by no means exclusive to roadside breakdown because clutch plates and gearbox problems were also plentiful, as was running out of fuel.

With the advent of newer cars, the race for the most fuel efficient and least expensive car was on. When fuel and air stoichiometrics were at its peak, car manufactures started producing cars with a 'Space Saver Biscuit Spare Wheel' which took several kilograms of weight out of the trunk, This made the car a tad lighter, slightly more fuel efficient and ever so slightly, cheaper to produce.

Today, almost a third of all new cars don't even have a spare wheel; instead they may be equipped with a can of self inflating puncture-repairing foam, or an electrical air compressor with some sealant kit to temporarily fix a flat tyre. Both options are evidently cheaper than a Space Saver Biscuit Spare Wheel and lighter.

However, believe-it-or-not, the more expensive cars today, are sold without  a spare wheel, instead they are fitted with “run-flats”. In a nut-shell, run flats are special pneumatic tyres, designed to resist the effects of deflation when punctured, yet enables the car to  be driven at reduced speeds of under 90 km/h for a distance of up to 80 km. The speed and distance of course to the nearest tyre repair shop, is subject to the type and quality of the “run-flats”.  So, once again the manufacturer saves the cost of supplying a spare wheel.

Be that as it may, snapped fan belts  often causing the engine to overheat, sometimes resulted in a  blown  cylinder head gasket. Subsequently, the modern day electric radiator fan has totally supperceeded the belt driven fan and as a result, burst radiator hoses, corroded, leaking water pumps and welch plugs have  became the primary cause  of blown cylinder head gaskets. The other bugbear is oil leaks that weren't timeously attended to, currently trending as the most common cause of seized engines. 

With the abundance of electronics fitted into cars, the alternator  and its voltage regulator have  became a lot more more troublesome than ever before. Obviously due to the additional electrical load.  Alternator  problems are closely followed by starter issues when either its brushes or its  bendix reaches its end of life.   

Both types of problems have resulted in batteries being replaced prematurely and sometimes unnecessarily. Brakes and Turbos also give their fair share of problems, but none of these problems comes close to the new type of roadside breakdowns caused by the OBD-II system.

The most common cause of  breakdowns today, is the Electronic Power Control (EPC) light; not that the light is the cause of the problem. The Electronic Power Control (EPC) light is only an advisory light, drawing your attention to a possible malfunction or  pending problem or  already existing problems.

When the Electronic Power Control (EPC) light comes on, without the ESP or Check  engine light, the car is normally still driveable, even if it goes into limp mode. But when accompanied by the ESP and or CEL (check engine light) the car may refuse to start as its inhibited by the Electronic Computer Unit (ECU). 

When this happens, the only solution is to secure a rollback to fetch the car and take it either to your service agent / mechanic or your home, so that you can tend to the problem yourself. 

There is no way you'd be able to effect repairs to your car yourself without a OBD II scanner   that would direct you to, or confine your repair to a certain area of the engine. 

Below are a few sample yet partial ODB II diagnostic scans  for Electronic Power Control (EPC) problems. 

This for a 7N0 - VW Passat.
Address 01: Engine (CDL)       Labels: 06F-907-115-CDL.clb
   Part No SW: 1P0 907 115 AB    HW: 8P0 907 115 B
   Component: 2.0l R4/4V TFSI     0020  
   Revision: 5BH20---    Serial number: 0000              
   Coding: 0303004C18070160

1 Fault Found:
008487 - Accelerator Position Sensor 2 (G185) 

               P2127 - 002 - Signal too Low

Electronic Power Control (EPC) problem  for a 1J - VW Golf.

Address 01: Engine Labels: 06A-906-032-AWP.lbl

Part No: 06A 906 032 RN

Component: 1.8L R4/5VT G 0001 

Coding: 07510

18047 - Accelerator Position Sensor 1/2 (G79/G185) 
            P1639 - 35-00 - Implausible Signal
18042 - Accelerator Position Sensor 2 (G185) 

            P1634 - 35-10 - Signal too High - Intermittent

Electronic Power Control (EPC) problem  for a 7L - VW Touareg 

Address 02: Auto Trans        Labels: 09D-927-750.lbl
   Part No: 09D 927 750 AN
   Component: AL 750 6A           0546  
   Coding: 0004153


1 Fault Found:
00777 - Accelerator Position Sensor (G79) 

            004 - No Signal/Communication - MIL ON

NB! The Automatic Transmission module and not the Engine Module detected this accelerator sensor problem.

 

Electronic Power Control (EPC) problem 1H - VW Golf/Vento III
Address 02: Auto Trans       Labels: 01M-927-733.LBL
   Controller: 01M 927 733 CT
   Component: AG4 Getriebe 01M    3363
   Coding: 00000
    

1 Fault Found:
00518 - Throttle Position Sensor (G69)

            16-10 - Signal Outside Specifications - Intermittent

NB! The Automatic Transmission module and not the Engine Module detected this accelerator sensor problem. Here the Throttle position sensor instead of the Accelerator sender is the cause of the problem.

Electronic Power Control (EPC) problem  for a 9M - VW Jetta IV.
Address 01: Engine Labels: 06A-906-032-AWP.lbl
Part No: 06A 906 032 RN
Component: 1.8L R4/5VT G 0001 
Coding: 07510

1 Fault Found:
18047 - Accelerator Position Sensor 1/2 (G79/G185) 

P1639 - 35-00 - Implausible Signal 

Electronic Power Control (EPC) problem  for a 8E - Audi A4.
Address 01: Engine Labels: 06C-909-559-ASN.lbl
Part No SW: 8E0 909 559 D HW: 8E0 909 059 
Component: JHM V3/9X G 0003 
Coding: 0016751

2 Faults Found:
18047 - Accelerator Position Sensor 1/2 (G79/G185) 
P1639 - 008 - Implausible Signal - Intermittent
18047 - Accelerator Position Sensor 1/2 (G79/G185) 

P1639 - 008 - Implausible Signal - Intermittent - MIL ON

Electronic Power Control (EPC)  for a 8P - Audi A3.
Address 01: Engine Labels: 06A-906-033-BGU.lbl
Part No: 06A 906 033 DS
Component: SIMOS71 1.6l 2V 5559 
Revision: --H03--- Serial number: AUX00000
Coding: 0000071

4 Faults Found:
18047 - Accelerator Position Sensor 1/2 (G79/G185)

P1639 - 008 - Implausible Signal - Intermittent

Electronic Power Control (EPC) problem  for a 9M - VW Jetta IV

Address 01: Engine Labels: 06A-906-032-AWP.lbl

Part No: 06A 906 032 LP

Component: 1.8L R4/5VT G 0005 

Coding: 07500

18042 - Accelerator Position Sensor 2 (G185) 
P1634 - 35-00 - Signal too High
18039 - Accelerator Position Sensor (G79) 

P1631 - 35-00 - Signal too High

 Electronic Power Control (EPC) problem  for a 1C - VW New Beetle

Address 02: Auto Trans Labels: 01M-927-733.lbl
Part No: 01M 927 733 EN
Component: AG4 Getriebe 01M 4108
Coding: 00000

1 Fault Found:
00518 - Throttle Position Sensor (G69)

16-10 - Signal Outside Specifications - Intermittent

NB! Once again the Automatic Transmission module  detected this Throttle position sensor instead of the Engine Module detecting the Accelerator sender to be the cause of the problem.

___________________________________

As can be seen from the data above,  there are essentially 3 types of  DTC errors responsible for triggering the EPC light, though not exclusively. P codes  P1630 and P2122;  P1631 and P2123;  P1632 and P1861 are essentially the same and applies to sender 1. 

As can be seen below.
P1633 and  P2127;  P1634 and P2128; P1639 and P2138 are essentially the same but applies to sender 2. There are also several other DTC errors that can and trigger the EPC and or along with the ESP, and or with the CEL.

Accelerator Pedal Sensor 1

P1630 - Accelerator Pedal Pos. Sensor 1 (G79), Signal too Low

P1631 - Accelerator Pedal Pos. Sensor 1 (G79), Signal too High

P1632 - Accelerator Pedal Pos. Sensor 1 (G79), Power Supply Malfunction

P2122 - Accelerator Pos. Sensor 1 (G79), Signal too Low

P2123 - Accelerator Pos. Sensor 1 (G79), Signal too High

P1861 - Accelerator Pos. Sensor 1 (G79), Error Message from ECM

Accelerator Pedal Sensor  2

P1633 - Accelerator Pedal Pos. Sensor 2 (G185), Signal too Low

P1634 - Accelerator Pedal Pos. Sensor 2 (G185), Signal too High

P1639 - Accelerator Pedal Pos. Sensor 1/2 (G79) / (G185), Implausible Signal

P2127 - Accelerator Pos. Sensor 2 (G185), Signal too Low

P2128 - Accelerator Pos. Sensor 2 (G185), Signal too High

P2138 - Accelerator Pos. Sensor 1/2 (G79) + (G185), Implausible Signal

Throttle Position Sensor

16505/P0121/000289 - TPS (G69): Implausible Signal
16506/P0122/000290 - TPS (G69): Signal too Low
16507/P0123/000291 - TPS (G69): Signal too High

Throttle Angle Sender 1

17950/P1542/005442 = Angle Sensor 1 for Throttle Actuator (G187): Implausible Signal
17951/P1543/005443 = Angle Sensor 1 for Throttle Actuator (G187): Signal too Small
17952/P1544/005444 = Angle Sensor 1 for Throttle Actuator (G187): Signal too High  

Throttle Angle Sender 2

16605/P0221/000545 - Angle Sensor 2 for Throttle (G188): Signal   Implausible 
16606/P0222/000546 - Angle Sensor 2 for Throttle (G188): Signal Too Low
16607/P0223/000547 - Angle Sensor 2 for Throttle (G188): Signal Too High

Depending on the model of your vehicle, its Throttle position sensor (TPS) lowest output voltage should be around .17 Volt and when the Electronic Control Unit (ECU) detects that it has dropped below that, then it will trigger either a P0122 or P0222 code.  High signals are not common but they do occur. 

 

As can be seen from the above data the error signal is either too low or to high or intermittent/implausable. Bearing in mind that a constant 5 volts is supplied by the ECU via a High-side or Low-side driver to the each of these potentiometers (senders). Loss of the voltage or even intermittently loss will trigger the EPC light and enter into "limp mode".

By implication  the monitored output is in 1 of 3 states, viz, low, high, or intermittent. In order to determine these states, the ECU needs a reference to compare these signals against. Each sender therefore act as a reference for another and any discrepancy between the two can result in an EPC error and subsequent limp mode. 

Replacing the Accelerator Pedal sensor (potentiometer)  unit normally fixes the EPC problem, but limp mode can also be caused by the throttle butterfly potentiometer.  And like I mentioned before, an OBD-II diagnostic tester would make this repair a lot easier and a lot faster.


NB! When your car goes into "limp mode", you may have  a lit   "Engine Management Light" (EPC icon) and or a "Electronic Stability Light" (skidding car icon) and or a "Engine Control Lamp" (engine icon) or any other combination thereof.  

Even Earthworks machinery are fitted with OBD-II so that exhaust emissions can be controlled but when there is a problem in the OBD-II system, invariable these machines would have to go on a roll back and taken for repair.

 

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VW Beginings

VW's humble beginings

Volkswagen, derived from the German words "Folk's Wagon" or "People's Wagon," traces its roots back to 1937 when it was founded as a pivotal player in the automotive industry. Over the decades, it has grown into the largest car manufacturer globally, boasting an extensive lineup of vehicles. One of its most iconic creations is the Volkswagen Beetle, which has left an indelible mark on automotive history.

VW Beetle 1937

Commissioned by Adolf Hitler, the leader of Nazi Germany, the Volkswagen Beetle was conceptualized and designed by Ferdinand Porsche, the renowned Austrian-German automotive engineer and founder of the Porsche car company. 

The Beetle first rolled off the production lines in Germany in 1937 and remained in production until the late 1970s. However, its legacy endured, with production continuing at Volkswagen's Puebla facility in Mexico until 2003. In total, over 21 million Beetles were manufactured, earning it the affectionate moniker of the "poor man's Porsche."

The Beetle's success paved the way for other Volkswagen models, including the Type 2, famously known as the VW 'Bus' or Microbus, and the stylish Karmann Ghia. Subsequent iterations, such as the Type 3 'Ponton' and the Type 4 411/412 family car, further solidified Volkswagen's reputation for innovation and versatility in the automotive market.

Despite its iconic status, Volkswagen eventually ceased production of the Beetle, citing feasibility concerns in an increasingly competitive market. As other car manufacturers introduced similar-sized four-door vehicles, the Beetle, Karmann Ghia, and 'Ponton,' all two-door models, faced challenges in meeting the evolving needs of consumers, particularly in the taxi industry. The practicality of four-door vehicles for passenger transportation outweighed the convenience of two-door models, leading to a shift in consumer preferences.

This transition marked a pivotal moment in Volkswagen's history, reflecting the company's adaptability to changing market dynamics while staying true to its commitment to innovation and excellence in automotive engineering. While the Beetle era may have drawn to a close, its legacy lives on, serving as a testament to Volkswagen's enduring impact on the automotive landscape.

 The New Beetle was manufactured from 1998–2011 which included  a 2-door coupé/ convertible but wasn’t  a replacement for the original Beetle,  the VW golf and VW Passat was.  The original Beetle, the VW Golf  and the VW Passat were the three top VW cars in the history of the automaker, all three of which stood out for its simplicity, affordability and quality for more than thirty years.  The Volkswagen Beetle  is a two-door economy car, intended for five occupants  and sported an air-cooled rear mounted engine.

What does it mean if the EPC warning light comes on in a Volkswagen?

What does it mean if the EPC warning light comes on in a Volkswagen?

Since the inception of the motor vehicle, several manufactures have claimed that their brand of car, has sold the most units globally. But since there is no definitive comparative yardstick to measure the exact amount of units sold,  Volkswagen claimed that their Volkswagen Beetle is the "bestselling car in history", considering they had sold more than 21 million units. To be more exact, The New York Times, date July 31, 2003 stated that the very "Last Volkswagen Beetle" manufactured was in fact number 21,529,464. 

Ford on the other hand manufactured their 1 millionth Model T's during the last month of 1915, with total sales of 15 million units produced by 1927 when they ceased production. In 1972 Volkswagen broke Ford's record when their 15,007,034th Beetle came off the production line in Puebla, Mexico. 



Be that as it may, Toyota boasts that in reality, their Toyota Corolla is the "bestselling automobile in the world", after reaching their 40 millionth unit in July 2013. But regardless of their claim, Volkswagen is undoubtedly still the "bestselling automobile in the world" seeing that the Volkswagen Beetle didn't change its shape or form since 1945 up to and including 2003, whereas Toyota used their Corolla label for eleven generations of Toyota cars, built since 1966 and this very Corolla label is still in common use. Non-the-less, statistically Volkswagen has been the best selling car globally until late 1998; meaning the Volkswagen Beetle remains the "bestselling vehicle ever". 

Enter the Volkswagen Kombi, Volkwagen City Golf, Volkswagen Fox, Vokswagen Jetta, Volkswagen Golf, Volkswagen Polo, Volkswagen Passat, Volkswagen Kombi, Volkswagen Sharan, Volkswagen  Toureg, Volkswagen Amrok, Volkswagen Transporter and the list goes on. However this entire Volkswagen fleet doesn't come without their fair share of  problems. The most common of which is probably the EPC light accompanied by limp-mode home.

What is the VW EPC Warning Light, 

The Electronic Power Control warning light, is commonly known as the EPC warning light. It's a dashboard warning indicator that suggests that there may be a problem with your Volkswagen’s throttle system. The throttle system consists of the accelerator pedal, the throttle body, traction control, cruise control, and the ECU, which is collectively called the drive-by-wire system. 
The drive-by-wire system is also sometimes referred to as an Electronic Throttle Control (ETC), roughly described as a technology that electronically "connects" the accelerator pedal to the throttle, instead of a mechanical linkage. 

In a drive-by-wire system, an electric stepper motor determines the angle of the throttle valve. How wide it opens or closes, is calculated by a —closed-loop control algorithm— software controlled embedded system built into the ECU. The ECU makes decisions based on various input data from several sensors, among which are, the accelerator pedal position sensors, engine speed sensor,  vehicle speed sensor, and the cruise control switch. The Electronic Control Unit (ECU) can also be described as a computerized ignition / engine management system  that operates in conjunction with the stability and cruise control systems. When the EPC light comes on, it means the problem is not emission related, whereas the Check Engine Light (CEL)indicates emission related problems but when it lights up, can be accompanied by the EPC light. If the EPC warning light comes on in your vehicle, it is important to have it seen to as soon as possible, because it you don't invariable it's going to trigger again when you least expect it.

EPC Car Warning Light

When the EPC light comes on in your Volkswagen, its throttle may be limited in power, yet have sufficient power to drive the car to a dealership or mechanical workshop, but it shouldn't be driven elsewhere. This is called limp-mode-home. Limp mode home is  inherent in its the software design in order to to protect the car from run-away and  its passengers from possible injury. Volkswagen cars equipped with a Electronic Stability Program (ESP) program, will display its ESP light instead of the EPC light and may automatically trigger the car into limp-home mode. 

Vehicles fitted with Traction Power System (TPS) are also prone to enter into 'limp-home-mode'  which effectively prevents software glitches from initiating or activating unintended acceleration.  In 2011 the U.S. National Highway Traffic Safety Administration (NHTSA) commissioned a team of NASA software engineers to evaluate software of late model year Toyota and Lexus vehicles, alleged to be the cause of  unintended acceleration collision, which caused the death of a passenger in a September 2007. 

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Automotive Electronic Components

Automotive Electronic Components

Admit it or not, we all love the new creature comforts of our modern day cars, all of which have become increasingly sophisticated.  Those seat warmers in the cold of winter, the climate control in mid summer, the air suspension on those bumpy roads, the infotainment systems with integrated GPS so that we never get lost again; and the on-board video player for those times we had to patiently sit and wait in our cars for our loved ones. ECU controlled fuel injection put an end to idling the car in the morning to get it to the appropriate operating temperature. Power steering and assisted parking makes both driving and parking a breeze. ABS and traction controls ensures that your car stops and corners without incident. 

Not to mention cruise control, the increased horsepower, the additional  safety features and the overall improved spatial comforts. And the list goes on. All of this was made possible by electronics, in the name of safety. Safety in the form of Safety Restraint Systems (SRS), Front and side airbags, early crash sensors and active front seat head restraints, to  mention but a few. 

On-Board Modules

Electronic engine management systems, carputer modules, telematic systems and other electrical components constitutes a sizeable percentage of our cars, collectively affording us the aforementioned comforts and conveniences. Besides, modern cars are loaded with code; and the number of electrical components in modern cars are on the rise, constantly and consistently increasing in number, and their failure can more often than not affect our driving safety. These electronic components can easily malfunction, either due to water ingress during wet weather conditions, or due to excessive vibration due to bad road surfaces, or just through general wear and tear. Most of these components are cheap and relatively easy to repair and replace but isolating the correct one can sometimes be trying. In a nutshell, modern day cars are seriously complicated, since they are not just computers on wheels but entire computer networks on wheels. Be that as it may, it is a well known fact that computers do crash, software have glitches and networks go off-line.

How safe is safe?

But, the million dollar question remains; are these electronic devices really safe or are they as safe as the car manufactures would like us to believe they are.  How safe is it when you're overtaking on a single lane highway at 100km per hour and the car goes into 'limp mode' or the engine just switches off and refuses to restart?  How safe is it when the steering wheel airbag explodes directly into your face for absolutely no reason? Its air pressure wave that's louder than a gun, is bound to temporarily deafen you and the smoke enveloping you would certainly disorientate you. These factors can contribute to you loosing control of the car through no fault of your own or even loose your life.  

How safe is it when you suddenly and momentarily loose steering control at high speed or whilst driving in fast moving traffic when your car doesn't react to your steering direction?  Or, how safe is it when your steering wheel suddenly goes stiff when turning (temporary loss of power steering)? How safe is it when your car randomly starts to jerk and switches off on a deserted road at night? 

How safe is your VW really, considering certain Jetta, Golf and Audi A3 models are being recalled for fuel leaks that can cause potential engine fires. Case in point, German supplier Continental Automotive GmbH has been supplying fuel tank polymer flanges that crack to five OEM parts supply companies at least 11 auto makers, VW, Audi and Porsche included.  What this means is that 
there are millions of cars of all makes and models that may have leaking fuel issues as we speak.

Electrical sub systems

As mentioned above, modern cars, can have as many as 200 small embedded electronic control units, better known as  (ECUs). Each module is in fact a fully fledged computer in its own right, overseeing one subsystem. Collectively they  have several functions, ranging from controlling the engine and or transmission, to controlling the immobilizer, to controlling the air bags, to unlocking doors, to controlling the radio, to managing the ABS, to managing the cruise control and such like. 

Most of these computer modules have input switches and or input sensors that can detect variables such as temperature, air pressure, braking, steering angle, voltages. All these computers are connected to a centrally networked  CAN bus that carries constantly varying data between them, in order to manage the car as it is being driven. The upside of this, is that the car can virtually drive itself but the downside is that when some essential module does go faulty, it would most likely shuts the car down which may also turn out to become an expensive repair.

Automakers are becoming more like 
assemblers and less like manufacturers

Essential components like headlights and spark plugs, ignition leads, wiring harnesses, relays and switches  can often be the first to go, but they are more electrical than electronic. Whereas the following list of sensors and actuators are totally electronic.

Air mass sensors (MAF) - electronic
Camshaft Position sensors - electronic
Crankshaft Position sensors - electronic
EGR Valves  - electronic
Knock sensors - electronic
Lambda (oxygen) sensors  - electronic
Throttle position sensors  - electronic
Wheel speed sensors  - electronic
Ignition Coils  - electronic
Glow Plugs  - electronic
Coolant temperature sensors  - electronic
ABS  actuators  - electronic
Injection valves - electronic
Solenoid valves - electronic
Anti-theft alarm  - electronic ... and the list goes on.

Since Automobile production requires several thousands of parts, most of these parts are not manufactured by the car maker but are supplied by auto suppliers. Hence automakers are becoming more like assemblers and less like manufacturers because Auto Megasupplier's  contributions have drastically increased from about 60% in the mid '90s to above 85% in 2017.  Among these auto megasuppliers are companies like:-

Robert Bosch supplies (Gasoline and diesel systems, chassis system controls, electronics,  exhaust gas turbochargers, steering systems, starter motors and alternators,   etc), 

Draexlmaier Group (wiring harnesses,  interior systems, cockpit and door modules, etc.),

Royal Philips Electronics (Lighting, car radio integrated circuits, liquid crystal displays, etc.)

Infineon Technologies (Microcontrollers, intelligent sensors; power semiconductors, etc.)  

Hella ( Electronic & lighting components, etc.)

DuPont Automotive (polymers, elastomers, specialty chemicals, lubricants, refrigerants, etc.) 

SKF Automotive ( Bearings, seals, clutch assemblies, SKF Automotive drive-by-wire systems, etc.) 

Valeo SA (transmissions, Micro hybrid systems, etc.)  

Magneti Marelli (Lighting, powertrain transmissions, electronics, suspension systems,  shock absorbers, exhaust systems, plastic parts, etc.)

Continental AG (Instrumentation, stability management systems, chassis systems, safety system electronics, telematics, powertrain electronics, interior modules, etc.) 

Eberspaecher Holding GmbH (Silencers, catalytic converters, particulate filters, manifolds, vehicle heaters, electrical vehicle heaters, electronics, climate control systems, etc.)

CITIC Dicastal Co.  (Aluminum alloy wheels, aluminum casting parts, etc.)

Mobis North America (Chassis, cockpit & front-end modules; ABS, ESC, MDPS, airbags,  LED lamps, ASV parts, sensors, electronic control systems, hybrid car powertrains, parts & power control units, etc.)

That being said, there are so many of these components from auto suppliers that are troublesome. For example, batteries, starter solenoids, diodes and alternator voltage regulators and relays. Considering that the alternator is the heart of  your vehicle's electrical system and that the electrical load has substantially increased due to the glut of extra electronics, I would think that some manufactures would at least have a second alternator for redundancy. Even perhaps a redundant network so that an alternative data path is  available if the wiring harness goes faulty. Or even dual temperature sensors, or dual camshaft sensors, etc. It would do marvels for reliability.

Volkswagen is recalling some 766,000 cars globally for a software upgrade to their "anti-lock braking system".

Volkswagen is recalling 8.5 million diesel cars across the European Union  due to the "emissions scandal".

Volkswagen is recalling some 90,000  gasoline powered VW Beetle, VW Golf, VW Jetta and VW Passat with 1.8T or 2.0T engines sold between 2015-2016, because the rear camshaft lobe has the tendancy to unexpectedly snap-off from the camshaft resulting in "loss of vacuum to the brake booster", implying inefficient braking and an increased risk of a crash.

Volkswagen recalls some 280,000 cars for fuel leaks.

Honda recently recalled 1.2 million  from the 2013-2016 model Accords years, citing 'faulty battery sensors'.


Ford South Africa recalled 2.0-litre diesel-powered Kuga SUVs to resolve a potential "brake problem". 

VW electric fuel pump

VW electric fuel pump 

VW electric fuel pumps are troublesome and VW, Audi, Seat and Skoda cars are notorious for fuel pump problems. Fuel pump problems commonly affect the Volkswagen Polo Classic 6n, the VW Polo 9N, the VW Bora, the VW Passat, the VW Sharan, the VW Caddy, the VW Golf, the Volkswagen Touareg  and the  VW Beetle, among several other. Its effects can range from intermittent no starting to stalling whilst driving, though most clients would complaint that the car jerks and stall and then just shuts off. However it's not always the fuel pump that's to blame. 

VW fuel pump relay

The VW fuel pump relay is another culprit that goes faulty or rather its external contact terminals tend to burn. So if your car wont start, give the Fuel Pump Relay #409 (1J0 906 383 C) or #410 (6N0 906 383A) a knock or two with a screwdriver handle and should the car start, then it's most likely a bad contact on one of its 7 spade terminal. Remove the relay and see if any of its terminal pins have burnt brown. If not, the relay's internal contacts are probably faulty and needs to be replaced. One consolation is that the relay is fairly cheap and it can be bought on-line at ebay.com for as little as $15. However, a VW fuel pump price on the other hand, is ridiculously priced especially  considering I've had a clients who had to have two fuel pumps replaced in under 9000 km. I don't think they are quality pumps.

When our VW Caddy's fuel pump started to give-in, it presented itself as an occasional engine misfire when pulling away from a stop street or traffic lights. The engine misfire became progressively worse over time, so it was booked-in for a service, for spark plug replacement, oil drain and oil  filter replacement, etc.  At this time we didn't know that the engine misfire was caused by the fuel pump. The day the Caddy was returned, it drove fine for the first two hours then started to misfire as it did before, but thereafter the fuel pump started sounding like a hoover vacuum cleaner. 

I knew it was the fuel pump because I've heard this sound before on both a Polo 1.4 Trendline and a Jetta 1.8 which at the time turned out to be the fuel pump. Anyway, the noise from the fuel pump was really high pitched and annoying, After several hours of driving it became unbearable so the Caddy went back to the mechanic who then diagnosed the fuel pump as faulty. After the fuel pump was replaced the noise disappeared and the miss was gone as well. My friend also  encountered the "hoover vacuum cleaner" with his Caddy but after a few days it just disappeared, so now he occasionally experiences starting problems.

VW  Fuel Pump Relay 409 / 410

VW  Fuel Pump Relay Part # 1J0906383B (409) is a 12V 40A relay with 7 spade terminal connectors, 2 Wide, 2 Standard and 3 mini. The same relay is  installed in VW Polo Mk3, VW Jetta, VW Golf Mk4, VW bora,VW beetle, Audi A3, Audi  TT, Seat Leon,  Skoda Octavia,  VW Sharan and VW Passat, etc.


VW  Fuel Pump Relay Part # 6N0906383A (410) is installed in VW Polo 6N, VW Golf Mk4, VW Lupo 6X, Skoda Fabia 6Y, VW Sharan 7M, AUDI A2, SEAT Arosa, SEAT Alhambra, VW Golf GTI, VW Passat and VW Polo Mk3, etc.

Replacing a fuel pump

Remember that the VW electric fuel pump relies on fuel passing through it for both cooling and lubrication. If or when running the fuel pump dry, fuel starvation can accelerate  internal component wear and may cause  the fuel pump motor to overheat and burn out. Electric fuel pumps run from the moment the ignition is switched on, so its fairly obvious that after a few years of operation their armature bushings, gears, commutator and brushes will suffer wear and tear, causing a gradual loss of pressure. Loss of fuel pump pressure commonly causes the "EPC" light to come on. A fuel leak or an Evaporative Emission System (EVAP) leak would also turn on the "EPC" light as well as the "Check Engine" light because the low inlet manifold pressure would upset the engine's air-fuel ratio and degrade engine performance and reduce fuel efficiency.  It would also diminish  power and acceleration, and possibly even cause stalling.  So if you need to replace your VW electric fuel pump, make absolutely sure you depressurize the fuel system before disconnecting the fuel lines. The easiest way to do this is to remove the fuel cap, remove the electric fuel pump fuse or relay and crank the engine a few times. 

Faulty Fuel Pump Flanges

There is currently a VW / Audi fuel pump recall, though its not necessarily the pump that's defective but rather faulty flanges manufactured by German supplier Continental Automotive GmbH. Apparently they've been supplying VW, Audi and Porsche with flanges that seem to crack and cause fuel leaks and potential fires. Apparently Continental sold the potentially faulty flanges to eleven automobile manufacturers and five OEM parts supply companies. Audi, Ford,  Fiat Chrysler, General Motors,  Jaguar-Land Rover, Lamborghini, Mercedes-Benz, McLaren, Porsche, Volvo and VW are just some of the automakers who used these industry-standard polymer flanges but other automakers may possibly also be at risk. 

Meanwhile Volkswagen, Porsche and Audi already recalled nearly a half-million vehicles because of leaky flanges, that cover fuel tank openings and is used for the fuel pump and other items. U.S. safety regulators are currently trying to track down gas tank flanges that may crack and cause fuel leaks on what could be millions of cars of all makes and models.

Continental Automotive GmbH supplied millions of fuel pump flanges to 11 car makers that can cause a potential fire. Is you car one of them?

— Faried (@Syba_seca) July 10, 2017

Volkswagen Electrical Problems

Volkswagen Electrical Problems

Electrical problems will invariably affect each and every new Volkswagen vehicle on the road today.  Generally, electrical problems are relatively easy to trace and repair, if you know what you doing, but it can be a nightmare when the faults present themselves as intermittent, especially considering cars have now gone CAN Bus, LIN Bus, Byteflight, MOST, Flexray, Zigbee, etc. VW EPC problems tend to be seriously intermittent, making every VW with an EPC issue a real bitch to diagnose.  Of late, more and more VW cars seem to be having EPC trouble among other bizarre electrical problems and very surprisingly, the VW service centers seem unable to repair them. 

Virtually everyone I know who has had an EPC issue, had to take their cars for repairs at least three to four times for exactly the same fault.  There are also numerous VW, SEAT, SKODA and Audi owners, who spent enormous amounts of money on replacement of "EPC issue causing components", yet the EPC faults remain. Essentially they lost money but I normally say they didn't loose money but bought experience and they paid dearly for it. Then there are others who are still waiting on the VW service agents / or some mechanic for their EPC problems to be solved after several months, a year and in some cases even longer.  

There was a time when virtually every electrical issue or loom (wiring harness) problem was associated  with the  FIAT brand. People even ascribed a nomenclature to FIAT - "First In All Troubles". However, it seems like Volkswagen  subsequently bought that patent, and now owns all right to it.

Electrical problems have never been as common place as they are today.

Let me give you an example, the wiring harness between the alternator and  the a  high voltage fuse box mounted on the battery of the VW Beetle has a tendency to melt or it just start to burn. It's a very well known problem and is also really common. It the  main reason that so many Beetles have burnt to a crisp. The Beetle wiring harness running between turn signals / headlights and the ECM is also troublesome -intermittent. The wiring harness resistance between the injector and the ECM changes over time from 1 ohm to above 30 ohms. The wiring harness resistance between the alternator and the battery also increases due to failing fans thus causing excessive current draw resulting in the wiring harness  over heating then melt.

I've seen VW Polo and VW Passt headlight wiring harness melt. The connectors tend to melt due to the type of plastic used and can be traced back to either arcing / overheating of the the bulbs or shorting out of deteriorated wiring. VW Passat coil pack wiring harness also prevents the car from starting and when water enters the wiring harness in the cowl area beneath the windshield,  it caused a short that normally damaged / corrodes the electronic control module. 

Both the Volkswagen CC and the Golf Mk5 GTI now seem to have throttle body wiring harness issues causing the EPC light to switch on and make the car go into limp mode. But there is no fault code that tells you the wiring harness is faulty or intermittent. Another VW CC harness problem to be on the lookout for, is the trunk lid harness that physically breaks over time  due to opening and closing of the trunk. A common problem on VW Pasat is the ignition wires that breaks inside its insulation, resulting in misfires.  VW sells a six pin throttle body sensor connector kit with yellow wires (below) that needs to be spliced onto the wiring harness to circumvent EPC issues when presented with wiring harness / G187 & G188 DTC errors.

Throttle body rewiring kit

Audi throttle body connector kit.  The wires kinda looks like single mode optical fibre cables along with  fusion splice protection sleeves

VW also sells a  six pin accelerator pedal  connector (below) that needs to be replaced as a solution to EPC problems when presented with wiring harness and G79 & G185 DTC errors. There is a likelyhood that this culture of poor quality wiring harnesses has spilled over into all the other VW models as well. To make matters worse, the newest mania among vehicle makers like Honda, Subaru and Toyota  for example,  are to use eco-friendly soy-based insulation wire for their engine wiring harnesses. VW's, Audi and Porsche, uses a soy based wire sheath to encase the engine harness. 

The six pin throttle pedal connector the goes intermittent causing EPC problems.

As a result, rats and squirrels are attracted by the aroma of the wiring harness and nibbles off the tasty insulation causing the bare wires to short out. Apparently these soy-based wire coverings are totally irresistible to rodents. As proof to this, several VW owners who have had electrical problems with their cars have vacuumed rats nests along with dog food chunk from their engine compartments. Others have removed several hands full of hazel nuts shells from their air filter boxes  that squirrels made their haven.  

Replacement six pin connectors for VW Audi SEAT and SKODA

Be that as it may, modern day car soy based car components are not a first, during World War II, some U.S. states used soybean fiberboard for their license plates, which proved extremely popular among goats that made a feast out of them. All I can say is, that VW service centers are going to make a small killing by replacing wiring harnesses of the millions of VW on the road today. Personally, I think you whole biodegradable "go green thing" , "eco this eco that" is overrated and is  getting out of hand. 

Some time back, some Dummkopf  -Dr. Dieter Zetsche- at Mercedes Benz decided that all Mercedes Benz cars manufactured during 1992 – 1996 should be fitted with biodegradable wiring. This leap toward eco friendliness by Mercedes Benz was well-intended but those wiring harness prematurely disintegrated due to engine heat and caused untold electrical problems. VW should in fact take a lesson out of the Mercedes Benz's annals.

See the cracks and the brittleness of the wire insulation after just a few ears of use

However, there is a DIY remedy for biodegradable, rodent enticing soy flavoured wiring harnesses.  Honda Acura Acura supplies a genuine-OEM rodent-deterrent duct tape, which is treated with capsaicin, - super-spicy red-hot chili pepper compound - that deters rodent.  Wrapping you VW wiring harness before rats discover your car is the way to go. Enough said, so let me return the subject at hand. 

Spicy anti rodent insulation tape,

In the not too distant past, Volkswagen Jetta models manufactured between  January of  2005 and January  of 2006 were sold with a "defective door wiring harnesses". It wasn't that the harness was defectives in the sense of not working but rather the harness was made too short. As a result, thousands of Jetta owners were experiencing similar problems as the harness started to chafe and disintegrate through regular use.

Common experiences included loss of power to the door controls, failure of the power window controls, failure of the power mirror controls, failure of the fuel tank latch release, failure of the boot lid release. Other weird experience included loss of audio to the speakers, a tripped air bag light on dashboard, when locking the door with the key fob remote the radio to turn on, or the key fobs just doesn't work, also having to recharged the battery continually because it runs down overnight. The interior door-open lights wouldn't turn off  and neither would the buzzer, the sunroof opened randomly. The turn signal in the side mirror stopped flashing and neither would the hooter work but would beep at odd times when you least expect it.  The windshield wipers worked occasionally and the car alarm would trigger unexpectedly and repeatedly.

In fact most VW Jetta owners complained about loss of some or all of the controls located on the driver's door.  These  faults weren't confined to the driver's door, because it was purely a matter of time before the the passenger door also developed a short or an open circuit in  one or more of its electrical circuit. The only way to remedy the problem was to replace the  broken harness with a genuine VW replacement which turned out to be some 80 mm longer than those fitted in the Jettas doors.

VW Jetta Front door replacement harness

A class action suit was leveled against Volkswagen alleging that they knew the door wiring harnesses were deliberately  made too short at the time these Jettas were sold. It was further alleged that Volkswagen shortened the harness by 80mm was  so that they could save costs, which  would ultimately lead to premature breaking of the door wiring harnesses boosting replacement harness sales.

However, most other Volkswagens electrical problems can possibly be traced back to a a troublesome ground. Water somehow enters the ground wires, in the cowling below the windscreen traveling inside the wire insulation resulting in corrosion. Always check the ground connections located  under the battery tray, or ground connections underneath the air cleaner box, or located inside the windshield wiper cowling or in the engine compartment, or the ground connections on the steering column or behind instrument cluster.   Covering the ground connections with battery terminal grease should offset the corrosion, if any, Remember poor ground connections, can cause a multitude of problems if it they become loose, can cause anything from cam sensor codes, to instrument cluster problems like erratic speedometer display, to misbehaving fuel gauge, to a dead gear indicator light, to non operational windshield wiper,  to a flickering digital clock , etc. 

Volkswagens that are equipped with air conditioning  are subject to high ambient temperatures which often causes the battery to get drained whenever the radiator fan kicks in at full speed with the ignition shut off.  Under high heat conditions, the gas pressure of the refrigerant can activate the A/C high pressure switch, triggering the high speed radiator fan relay to activate the cooling fan. Volkswagen has subsequently recommended a replacement fan relay switch with other minor modification of the A/C high pressure switch wiring, to solve this problem.

Replacement Radiator fan control switch

Whenever your VW misbehaves and you cannot put your finger on it, the best thing to  do is to investigate every ground lug on every bit of the engine wiring harness that you can get at. Loosen it, cleaned it with a  wire brush and some emery cloth and if needs be replace ground lugs that are corroded and possible even the screw/ nut. Don't forget to retorque the nut to the requisite tension. It may even be beneficial to add a second heavy duty ground strap to decrease resistance if any. Heavy duty welding cable from a welders supply store is far more  tolerant to vibration than your average cheap jumper cable wire. Starting difficulties can often be traced / associated to a poor ground connection. 

Remember when repairing wiring harnesses that soldering is not the recommended nor the appropriate method of repairing  it.  Solder joints are not flexible and tend to break after  while due to vibration.  Always use insulated crimp lugs and bullets like these below on connecting terminals especially at ground distribution points.

Lugs, bullet and spade connectors for repairing ground connections.

There is a tendency among car manufacturers to  miniaturize the physical size of electrical connector contacts and thereby the oversize of the connector. The problem is that the surface area of contact is remarkably reduced and are thus prone to intermittent contact under vibration. This has now become very evident on the wiring loom connectors that interface with the throttle body and the accelerator pedal to the point that they need to be replaced when they go intermittent. Don't bother to spray them with contact spray, just replace them. they are cheap enough to buy rather than suffer constant EPC issues and they are even available on Amazon, ebay, DHgate, and other online auction.

@DomLittlewood I need your help on a case I have with Volkswagen. A Brand new Volkswagen Polo numerous electrical problems & now caught fire

— Deano Luke (@95deanluke) August 30, 2016