Friday, December 2, 2016



The year 2016 is fast coming to and end but will always be remembered as the year that Volkswagen AG  needed to reverse public perception over the diesel gate scandal that affected some 11 Million vehicles globally during 2015. With it's hands full with public apologies, court battles, falling share prices, Diesel vehicle recalls and general damage control caused by the negative impact to their brand after admitting  that they circumvented emissions standards; VW have been somewhat curtailed from their key business of manufacturing cars.

With the uncertainty regarding the future of diesel, especially considering that the mayors of Paris, Madrid, Athens and Mexico City pledged to ban all diesel cars by 2025. And with the ever looming legislative imperative to cut down on carbon dioxide (CO2) emissions and other harmful gases, automotive manufacturers as a whole have started to seriously invest in electric-powered-car technology. 

Volkswagen produced the Volkswagen e-Golf hatchback which is however not a purposely built electric car but rather shares the powertrain hardware of the Golf MK7 MQB (Modularer Querbaukasten) Typ 5G, but  fitted with an electric motor in place of its petrol/ diesel powered engine. The e-Golf is in direct competition with other purpose  built electric cars from  several manufacturer's vehicles, like the Renault ZOE hatchback, Hyundai Ioniq Electric, Tesla Model S hatchback, Tesla Model X SUV, BMW i3 hatchback, Nissan Leaf hatchback and the Kia Soul hatchback. Be that as it may, VW has sold more than 25 000 units worldwide since 2014. The VW e-Golf matches the competition in range, but the the battery management doesn't have an  active cooling system which seriously affects longevity. VW hasn't in anyway been innovative nor produced anything new. Their VW e-Golf doesn't offer anything more than the competition already does and certainly amounts to less bang for your buck. Apparently the Renault ZOE hatchback seems to be the pure electric vehicle that's leading the EV race in virtually all categories. 

However, VW has always been promoting “Clean Diesel” as an alternative to hybrid and electric vehicles, thus pushing their 2009–2015 Volkswagen Jetta 2.0L TDI, 2010–2015 Volkswagen Golf 2.0L TDI, 2010–2015 Audi A3 2.0L TDI, 2012–2015 Volkswagen Beetle 2.0L TDI, 2012–2015 Volkswagen Passat 2.0L TDI,  etc, globally. It has now come to light that not only has Volkswagen cheated on emission testing with the 2.0L TDI engines, but also on the 3.0L  fitted in the 2009–2015 Audi Q7 3.0L V-6 TDI, 2009–2016 Volkswagen Touareg 3.0L V-6 TDI, 2013–2016 Porsche Cayenne Diesel 3.0L V-6. 

Volkswagen had hardly settled to pay $14.7 billion and announced a buyback schedule, thinking  it was putting an end to the Dieselgate scandal when the German weekly newspaper 'Bild am Sonntag' and the 'Wall Street Journal', citing unnamed sources reporting that the California Air Resources Board (CARB) have found new Emissions-Cheat Device / emissions-lowering software on an Audi. Test results  revealed that the Audi was emitting less carbon dioxide than it did during normal use, but when the steering wheel is turned more than 15 degrees, this program would shut off, detecting that the test had completed. The Wall Street Journal alleges that Audi management specifically detailed the defeats during their meetings.

This affects all VW owners and by the looks of things, other car manufacturers have surpassed Volkswagen in several categories. Looking at comparisons in Overall, Reliability, Build Quality, Running Cost, Performance, Road Handling, Ride Quality, Ease of driving, Seat Comfort, Practicality, Car Tech, Volkswagen is either doing very badly or in some cases doesn't feature at all. Volkswagen was lying in 10th position on the top 10 selling cars globally but has subsequently been  surpassed by Tesla Motor Company, that is a new entry into the car market or rather the EV market.

Fortunately for VW, its subsidiary Audi is still in the race even though it lost 6% in sales compared to the previous year as can be seen on the "Cars Top 10" slide.  Porsche  is also in the running but there doesn't seem to be stats available as yet. Looking at the three stats sheets above, it can be clearly seen the VW lies 19th for Build Quality, 19th for Running Cost, 16th for Ride Quality but for Overall  and Reliability it doesn't even feature. What were we thinking when be bought into Volkswagen? I am seriously thinking of turning my VW Polo into an EV, then I won't have any more engine problems, especially not issues associated with that pesky EPC light and Limp mode home.

Thursday, December 1, 2016



Can you believe it, Volkswagen  cars are produced with cookie cutters! Ok, ok that's exaggerating it a bit. I just needed to stretch this  analogy so that you can stretch your  imagination.  Volkswagen AG (VAG) has use the A04 / PQ24 platform for several of their cars during 2001 - 2015. Hence it turns out that the VW Polo 9N1, VW Polo 9N2,  VW Polo 9N3, VW Polo 9N4, the Volkswagen Fox 5Z1,Volkswagen Fox 5Z3, the Skoda Fabia 6Y2, Skoda Fabia Sedan  6Y3, Skoda Fabia Combi 6Y5, the Skoda Fabia-2 542, Skoda Fabia Combi-2  545, the Russian Skoda Fabia-2  572, the Skoda Roomster 5J7, the Audi A2 8Z0, the Seat Ibiza-3 6L1 and the Seat Cordoba 6L2 all share many similar features and electronic modules, engine components, wiring harnesses, if not the same, perhaps even identical. By just looking at the four of them, it is easy to see this, except for cosmetic changes of course. But underneath their outer apparel they are the virtually the same car using the same mechanical and electronic spares.

Volkswagen subsequently revised  their vehicle platform naming and identification system, for their ultra-compact (city cars), super-mini cars, compact cars (small family cars), mid-size cars and their full-size luxury cars to  numbers that look like PQ24, PQ25, PQ34, PQ35, etc. PL45, PL46, etc, PL62,  PL64 etc. For the uninitiated it only brings about more confusion in an already confusing time of information overload.


"A01" platform for the Volkswagen Polo Mk1,
"A02" platform for the Volkswagen Polo Mk2 - Classic, 
"A03" platform for the Volkswagen Polo Mk3- 6N/6KV,
"A04" platform is now known as the PQ24  -  all cars listed above,
"A05" platform is officially the PQ25 - for Audi A1, VW Polo (6R) and  SEAT Ibiza (6J). 

But for now we are interested in the meaning of platform codes like PQ24, PQ25, PQ34, PQ35, etc. PL45, PL46, etc, PL62,  PL64 and see how it affects the VW Polo range of cars with regards to spares and repair procedures.  When deconstructing the platform codes, we discovered that the  nomenclature for PQ24 is derived as follows:-

P - stands for a passenger car platform
Q - (Quer in German) stands for a transverse engine
2 - stands for the platform size or class
4 - stands for the generation
Essentially implying a passenger car platform with a transverse engine, fitted into a supermini of the fourth generation (MkIV).
Meaning, one of the cars mentioned in the heading of this blog installment, since all of them are classified as supermini cars.

Whereas the nomenclature for PL45 is derived as follows:- 
P - stands for a passenger car platform
L - (Längs in German) stands for a longitudinal engine
2 - stands for the platform size or class
5 - stands for the generation
Essentially implying passenger car platform with a longitudinal engine, fitted into a mid-size cars of the fifth generation (MkV).
Meaning a Volkswagen Passat (3B) or a Audi A4 (8D), etc.

Whereas the nomenclature for PL64 is derived as follows:
P - stands for a passenger car platform
L - (Längs in German) stands for a longitudinal engine
6 - stands for the platform size or class
4 - stands for the generation
Essentially implying passenger car platform with a longitudinal engine, fitted into a full-size luxury car of the fourth generation 
Meaning a Volkswagen Phaeton, Audi A8, or even a  Bentley Continental GT, etc.

Platform nomenclature was decided because car manufacturers are determined to get a better return on investment by using the same robotic arms and software programming on their  assembly lines / conveyer belts to assemble a host of different vehicles that look similar, with predominantly the components.  Also meaning that the space needed to stock parts are greatly reduced because instead of stocking the same part for 15 different models they have to stock just just one.

Case in point is the Joint-venture between Volkswagen and Ford Motor Company for producing the  Volkswagen Sharan (7M), SEAT Alhambra (7M), and the Ford Galaxy (7M). Volkswagen also started a Joint-venture between themselves and Daimler AG, to produce the Volkswagen LT range and the Second and third generations Mercedes-Benz Sprinter. In a sense one can just call this badge engineering, because Mazda and Ford have also have had long-term alliances, making cars until their partnership dissolved. 

Wednesday, November 30, 2016



Pre OBD vehicles had no need for an EGC circuit because these older cars had large noisy engines, were relatively fast, were gas guzzlers and  were emitting noxious exhaust emissions as if nobody cared about the environment. When combustion takes place inside an engine's cylinders, nitrogen and oxygen combine to form various oxides of nitrogen; which are collectively termed NOx. NOx emissions are generated as a function of high combustion temperature, so when it was discovered that these noxious gas emissions (NOx) were partly responsible for damaging the ozone layer and contributing to global warming, the EPA recommended legislation for OBD/EOBD/OBD-II systems to be fitted into all cars built after 1996 in order to monitor exhaust emissions.  

VW Engineers then came up with an EGR circuit which took different forms and configurations and were often particular to the make, model and manufacturer of the vehicle. EGR can be achieved either internally by means of valve overlap, or achieved externally by means of a  simple arrangement of pipes and a sprung loaded mechanical valve or an electronically controlled solenoid valve. Some turbo charged engines incorporate a low and high pressure exhaust Gas Recirculation system whereas some non-turbo engines only use high pressure EGR. Engines with diesel particulate filter systems tend to use a fast switching electronically actuated EGR valve, whereas a pneumatically activated EGR valve is employed by several others. Some engines used vacumm controlled EGR and some use water-cooled systems, yet all designed to supplement the traditional air/fuel ratio and spark timing circuit. 

VW 2.5 TDI AXG, AHY &  ACV engine  Pressure Converters,
EGR Valve Control Solenoid, EGR Pressure Feedback Sensor
Today virtually every vehicle manufacturers employ exhaust gas recirculation (EGR) as an emissions control sub-system in their cars, which has become an integral part of OBD-II.  The OBD-II exhaust gas recirculation system monitor is responsible for determining the serviceability of the sensors, hoses, solenoids, valves and actuators that are part of the EGR system and any problem with them would most likely trigger a binary '1' in a readiness test. Readiness tests evaluate eight on-board monitors to gauge the integrity of the engine.  Having said that, On-board diagnostic monitoring predominantly applies to systems that are most likely to cause an increase in harmful exhaust emission and during roadworthy testing these systems are specifically checked to verify compliance with EPA / government regulations.

Modern day EGR circuits essentially consists of electronic components and intelligent computer circuitry capable of recirculating a precisely controlled amount of non-combustible exhaust gas back into the intake manifold. A sort of a feed-back loop if you like. The objective is to  attain  lower combustion temperatures  and obtain optimal NOx reduction at middle and high engine loads. Restated, the greater the EGR the lower the NOx. NOx is poisonous and it is in the interest of every vehicle owner to keep their carbon footprint to a bare minimum.

The components involved in the EGR circuit are, the Mass air flow rate (MAF) sensor G70, Engine Exhaust Gas Temperature (EGT) Sensor 1 G235, Exhaust Gas Temperature (EGT) Sensor 2, Exhaust Gas Temperature (EGT) Sensor 3 G495, Exhaust Gas Temperature (EGT) Sensor 4 G648, EGR Vacuum Regulator Solenoid Valve N18 / N121, Exhaust gas Heated Oxygen Sensor (HO2S) G39, Wastegate Bypass Regulator Valve N75, Hot-film air mass meter G70, Engine  RPM sensor and the position of the EGR Potentiometer G212. EGR Cooler Switch-Over Valve N345, which are all vehicle dependent. These transducers  assists the Engine Control Module to recognizes the position of the spring loaded valve plate so that it can adjusts the actuator (electric controlled motor) that in turn controls the gas return flow so that it can  mix with a portion of  fresh air entering at the intake manifold. This lowers the internal combustion temperature and reduces the formation of oxides of nitrogen and keep it well within the legal limit.

However, when this doesn't happen, Engine performance is un-noticeably lower, causing the Glow Plug Indicator Light to flash  continuously  in the case of diesel powered vehicles and the Engine management light in the case of gasoline powered vehicles. Meanwhile the ECU will also register a DTC in its non-volatile fault memory. In the event of a EGR malfuntion which wound't normally be noticed by  the driver if it wasn't for the instrument cluster light that flashes or stays on, don't just start replacing components. First and foremost clean out any carbon buildup with Wynnes EGR 3 cleaner, then check the sensor harness and their respective connectors and check solenoids for continuity.

The likeness of the EGR valve can be compared to the throttle valve, both are butterfly plates that are electronically controlled by the ECU causing them to open and close dependent on the calculated duty cycle of the generated drive pulse. The wider the throttle opens the higher the engine will rev, likewise the wider the EGR valve opens the better the engine performs and the less NOx it produces.


Error codes staring at P0400 - P0409 ranges from malfunction of N18 (EGR Valve) to low/high signals from G98 (EGR Temperature sensor) to spurious signals from G212 (potentiometer)

Error codes staring at P1400 - P1408 ranges from Electrical Malfunction, to   Short to Ground/ Positive, too low or high

Error codes  P042E &  P042F dictates that the Exhaust Gas Recirculation "A" Control valve is, Stuck Open and stuck Closed respectively.

Error codes   P045E & P045F dictates that the Exhaust Gas Recirculation "B" Control valve is, Stuck Open and stuck Closed respectively. ts fairly pevalent on VW Jetta.

Error codes P2BAB & P2BAC dictates on incorrect EGR Flow, that NOx levels have exceeded and that the EGR has been deactivated.  Its fairly prevalent on the VW Crafter.

Once your problem is solved, it is imperative that you put  your VW, Audi, Skoda or Seat  vehicle, through a drive cycle but remember the drive cycle is manufacturer specific and should be executed accordingly.

Friday, November 25, 2016



Owning a VW Polo is fairly easy but when the exorbitant costs of unforeseen repairs and regular servicing are added, it becomes really expensive. To make matters worse, with the regular petrol price hikes, maintaining that VW Polo can become a bit of a burden.  The distance traveled by the average motorist, based on "official trade figure"  is estimated at 20 000Km per annum which directly translates to about 1667km per month or 55 km per day. At the current price of petrol (R12.89 per litre), that 55km would cost you about R43.00 subject to your Polo's Km/litre average consumption and your personal driving style. Extrapolated over a period of one year would cost you a cool R15,480.00-plus per annum and over the 60 months finance period, a whopping R77,400.00.

Volkswagen  e-Golf EV Charger Connection

Suddenly a diesel powered VW Polo TDI seems more financially attractive, especially considering that its fuel consumption of 4.6 litres / 100 km is far lower than the 5.9 litres / 100km of the low end VW Polol 1.4 Trendline. If truth be told, its a saving of at least 25 percent comparatively speaking but it's really  not that cut and dried.  My hesitancy towards a Diesel Vehicle gravitates around the fact that Volkswagen as a company had 'cheated on the fuel consumption and emissions figures globally', so I'm wondering how true these stats released by Volkswagen really are. Surprisingly, independents tend not to do comparative consumption studies or rather if they do, they don't make the results public. However, my consolation is based on my wife's Mercedes Benz C250D,  that uses a sight less fuel than her previous petrol powered C230E model over the same distance. Besides, virtually every heavy duty delivery vehicle out there is diesel powered because big business would invariably choose the more economical option. 'Diesel vehicles also tend to be less troublesome than petrol powered trucks'. They may not be as fast as their petrol powered versions but they have enormous torque, far great than their petrol counterparts. Then there is always the turbo version to consider that is much faster. Be that as it may, I'm not completely convinced whether or not to go that route.

Petrol and diesel fuel consumption comparison chart

There is a third alternative that I should explored and that is an electric powered vehicle. I quite like the VW e-Golf because its completely silent. It goes up to an estimated 133km per charge which I deem sufficient for short distance city driving. Unlike other manufacturer's purpose built electric cars, the VW e-Golf is essentially a normal VW car with an electric motor sitting in place of a petrol or diesel engine, with the fuel tank space occupied by its battery pack. Several car manufacturers are currently producing a small number of electric vehicles but it's painfully obvious that their range will expand in the coming years. So it's a good idea to embrace the newer zero emissions electric technology now, rather than later, in preference of further polluting our eco-system  with carbon dioxide emissions. But these EV's are a lot more expensive than both the petrol and diesel versions and the cost of electricity for charging its lithium-ion batteries still needs to be added. There is a likelihood that government will subsidize electric cars above a certain price range. It would probably work along the lines similar to the Eskom subsidy which is available to those home owners who intend installing a heat pump in their homes. My hesitancy revolves around recharging the EV when not near the home-based power unit. Regardless,  it makes more sense to buy the electric car, rather than a petrol or diesel car? My biggest concern though, is that lithium-ion batteries are still in its infancy or rather hasn't  properly matured yet. Though, there is a battery leasing option that comes at a monthly cost which will bring the overall monthly cost to more than than of maintaining a diesel VW Polo. Somehow this EV isn't looking that great anymore. But what I need to say is that I am very impressed by the distance that the Tesla can go on a single charge, as well as the overall quality of their new battery pack.
This impressive 115-hp electric motor with 269nm of torque makes for a really enjoyable drive.

EV Fuel Cost Comparison Example
Combined Fuel Efficiency150Wh/km 8L/100km 6L/100km
Annual Mileagekm120,00020,00020,000
Annual Fuel RequirementLitres0,0016001200
Energy / Electricity Prices / Unit

Litre /KW11.7512.9810.69

Thursday, November 24, 2016



With Winter looming in the Northern Hemisphere and Summer looming in the Southern Hemisphere, our car air conditioners are going to be in big demand very soon. On a really hot day the temperature down here in the Cape can easily rise to 35 degrees celsius and the inside of any car would be roughly 3-4 degrees more. That's the kind of discomfort nobody has signed up for. The converse is just as true, I remember when I was in Germany a few years back, during November the temperature dropped right down to minus 24 degrees celsius and whilst in France it was around minus 4 degrees or less most mornings. Trying to brave such weather conditions without on-board creature comforts borders on insane. So while the temperatures hasn't peaked yet, there is still time to get your fan/blower fixed. 

Of late, somehow several VW, Audi, Seat and Skoda owners have been having issues with the fan/ac/blower not working or not working properly. On a previous blog I failed to add the fan/blower issue to the list of common problems, but believe me it is. Below are some questions asked by a few VW owners regarding their respective VW vechicle refering to the fan/AC/Blower motor.  Well the culprit is normally the Heater Fan Blower Motor Tandem Resistor with OE/OEM Number 6Q0959263A / 6Q0959263/6Q0 959 263 A, manufactured by Hans Pries. Alternatively the Hella brand replacement part with  part number 5HL 351 321-301 or 5HL351321-301. 

The speed of the 12V blower motor is controller via this series "blower resistor". It's a wire wound ceramic resistor and there does get quite hot on speeds position 1, 2 and 3. In the last position the resistor is bypassed. So if you blower isn't working on every speed it is most likely the resistor. However if you have an A/C with  a four speed switch and the blower doesn't work on any of its 4 positions, then its most likely the ground wire that's loose, burnt, poor contact, intermittent. Behind the fan switch there is a large 4 pin white molex connector and when its ground wire  overheats, it looks lightly toasted and sometimes makes intermittent contact. On some models the motor is isolated, so connect a jumper between the car body and motor earth, just to test. If the connector is faulty, the motor with spin. If it doesn't, check for 12V DC supply on the Red/White wire with a multimeter, if there is no supply voltage, check the fuse and the heater relay. 


Red/Black - 12V supply to switch from fuse/relay box
Black/White - position 1
Yellow/Black - position 2
Yellow - position 3
Brown - from blower motor to ground/earth

Red/white - 12V supply 
Blue - position 1
Green - position 2
Black - position 3
Red - position 
Brown - from blower motor to ground/earth

Blower motor series resistor can be found in the glove compartment on some models


My heater fan doesn't seem to be working properly, I can feel a small amount of air blowing but I don't hear the blower motor. Please help me!


Read the blog!


Just bought an Audi A2 2005 and discovered defroster/heat/AC doesn't work. Is this major or should I cancel the sale? 


Read the blog! 


I have problem with my Jetta fan/blower that stops working, it just switched off after only owning car for two months.  No DTC codes!


Read the blog!


I recently noticed my interior heater/fan was becoming weak, and stops altogether at low speeds. Must I replace the motor.


Its very likely that the motor brushes has reached end of life. I think a new pair will give you blower a new lease on life. You didn't indicate what car you have, because yours  motor can possibly be of the  sealed type, meaning you would have to replace the motor if and only if you've exhausted the above.


My Golf's fan/blower works OK, but  after a while it makes a really loud noise like its struggling to keep turning and then it switches off. However when I hit a speed bump in the road it gives me a fright when it just turns back on. Can you help?


Read the blog!


Just bought a VW caddy and the fan/blower seems lazy and makes a noise that varies between loud and quite, previous owner says there is a leaf that fell down the ducting and lying on the fan. I'm not convinced because sometimes when I turn on the blower, it doesn't blow at all. Any suggestions?


Read the blog!

The heater fan blower motor resistor is one of those items that works on a great many VW, Audi, Skoda and SEAT cars. The list below gives you some idea  how common the problem really is. When you suspect that your heater fan thermal resistor has gone faulty make certain the part number is the same as the one you replacing it with because there is a fair amount of variation  even though there is a degree of compatibility.

Audi, SEAT, compatibility list
SEAT and Skoda compatibility list
SEAT, Skoda and VW compatibility list.

AUDI A2 (8Z0) 1.2 TDI, AUDI A2 (8Z0) 1.4, AUDI A2 (8Z0) 1.4 TDI,  
AUDI A2 (8Z0) 1.4 TDI,  AUDI A2 (8Z0) 1.6 FSI,  

SEAT CORDOBA (6L2) 1.2,  SEAT CORDOBA (6L2) 1.2 12V,  
SKODA FABIA (6Y2) 1.0,  SKODA FABIA (6Y2) 1.2,  SKODA FABIA (6Y2) 1.2,  
VW FOX (5Z1) 1.2,  VW FOX (5Z1) 1.4,  VW FOX (5Z1) 1.4 TDI,  VW POLO (9N ) 1.2,  

SEAT CORDOBA (6L2) 1.4 16V,  SEAT CORDOBA (6L2) 1.4 16V,  
SEAT CORDOBA (6L2) 1.4 16V,  SEAT CORDOBA (6L2) 1.4 TDI,  
SEAT CORDOBA (6L2) 1.6, SEAT CORDOBA (6L2) 1.6 16V,  
SEAT CORDOBA (6L2) 1.9 TDI,  SEAT CORDOBA (6L2) 2.0,  
SEAT IBIZA IV (6L1) 1.2 12V,  SEAT IBIZA IV (6L1) 1.4 16V,  
SEAT IBIZA IV (6L1) 1.6 16V,  SEAT IBIZA IV (6L1) 1.8 T Cupra R,  
SEAT IBIZA IV (6L1) 1.9 TDI Cupra R,  SEAT IBIZA IV (6L1) 1.9 TDI Cupra R,  
SEAT IBIZA V (6J5) 1.2,  SEAT IBIZA V (6J5) 1.4,  
SEAT IBIZA V (6J5) 1.4 TDI,  SEAT IBIZA V (6J5) 1.9 TDI,  

SKODA FABIA (6Y2) 1.4,  SKODA FABIA (6Y2) 1.4 16V,  SKODA FABIA (6Y2) 1.4 16V,  
SKODA FABIA (6Y2) 1.4 TDI,  SKODA FABIA (6Y2) 1.4 TDI,  
SKODA FABIA (6Y2) 1.4 TDI,  SKODA FABIA (6Y2) 1.9 SDI,  
SKODA FABIA 1.6,  SKODA FABIA 1.9 TDI,  SKODA FABIA Estate (6Y5) 1.2,  
SKODA FABIA Estate (6Y5) 1.2,  SKODA FABIA Estate (6Y5) 1.4,  
SKODA FABIA Estate (6Y5) 1.4, SKODA FABIA Estate (6Y5) 1.4 16V,  
SKODA FABIA Estate (6Y5) 1.4 16V,  SKODA FABIA Estate (6Y5) 1.4 16V,  
SKODA FABIA Estate (6Y5) 1.4 TDI,  SKODA FABIA Estate (6Y5) 1.4 TDI,  
SKODA FABIA Estate (6Y5) 1.4 TDI,  SKODA FABIA Estate (6Y5) 1.9 SDI,  
SKODA FABIA Estate (6Y5) 1.9 TDI,  SKODA FABIA Estate (6Y5) 2.0,  
SKODA FABIA Estate 1.2,  SKODA FABIA Estate 1.2,  
SKODA FABIA Estate 1.4,  SKODA FABIA Estate 1.4 TDI,  
SKODA FABIA Estate 1.4 TDI,  SKODA FABIA Estate 1.6,  
SKODA FABIA Estate 1.9 TDI,  SKODA FABIA Praktik 1.2,  
SKODA FABIA Praktik 1.2,  SKODA FABIA Praktik 1.4,  
SKODA FABIA Praktik 1.4 TDI,  SKODA FABIA Praktik 1.9 SDI,  
SKODA FABIA Saloon / Sedan (6Y3) 1.2,  SKODA FABIA Saloon / Sedan (6Y3) 1.2,  
SKODA FABIA Saloon / Sedan (6Y3) 1.4,  SKODA FABIA Saloon / Sedan (6Y3) 1.4,  
SKODA FABIA Saloon / Sedan (6Y3) 1.4 16V,  SKODA FABIA Saloon / Sedan (6Y3) 1.4 16V,  
SKODA FABIA Saloon / Sedan (6Y3) 1.4 16V,  SKODA FABIA Saloon / Sedan (6Y3) 1.4 TDI,  
SKODA FABIA Saloon / Sedan (6Y3) 1.4 TDI,  SKODA FABIA Saloon / Sedan (6Y3) 1.4 TDI,  
SKODA FABIA Saloon / Sedan (6Y3) 1.9 SDI,  SKODA FABIA Saloon / Sedan (6Y3) 1.9 TDI,  
SKODA FABIA Saloon / Sedan (6Y3) 2.0,  SKODA ROOMSTER (5J) 1.2,  

VW POLO (9N ) 1.2,  VW POLO (9N ) 1.2 12V,  VW POLO (9N ) 1.2 12V,  
VW POLO (9N ) 1.4 16V,  VW POLO (9N ) 1.4 16V,  VW POLO (9N ) 1.4 16V,  
VW POLO (9N ) 1.4 FSI,  VW POLO (9N ) 1.4 TDI,  VW POLO (9N ) 1.4 TDI,  
VW POLO (9N ) 1.4 TDI,  VW POLO (9N ) 1.6 16V,  VW POLO (9N ) 1.8 GTI,  
VW POLO (9N ) 1.8 GTi Cup Edition,  VW POLO (9N ) 1.9 SDI,  VW POLO (9N ) 1.9 TDI,  
VW POLO (9N ) 1.9 TDI,  VW POLO Saloon / Sedan 1.4,  VW POLO Saloon / Sedan 1.4,  
VW POLO Saloon / Sedan 1.4 TDI,  VW POLO Saloon / Sedan 1.9 SDI,

Thursday, November 17, 2016



The final note on the preceding blog installment ended on 'scan for Diagnostic Trouble  Codes with a scan tool'. However before we start scanning it is important to note, that Vehicles from year 2000 are fitted with an EPC (Electronic Power Control) system, hence this exposée only applies to cars fitted with a obdii 16 pin female connector, identifiable by its  normally purple core, roughly the same purple of the 6-pin mini-DIN connector  of a personal computer keyboard.  This EPC system / Drive-by-Wire circuit (implying no throttle cable) is also known as the torque circuit. The EPC system controls the EPC light  which turns on if and when there is the slightest malfunction  in the Drive-by-Wire circuit. Any such fault will more than likely generate a DTC (fault code) in the ECM, which is stored in its non-volatile memory, meaning even if the battery is disconnected afterwards the DTC (fault codes) will persist. However, also note that when the battery is disconnected all driver learnt values particular to your driving style, will be erased. Disconnecting the battery may require resetting the convenience electronics, such as alarm, interior lights and the radio. So, most importantly if you don't have the radio code, practice caution because the radio will permanently lock-up hence it's a good idea to use a jumper battery or perhaps even a battery charger to maintain battery power whilst replacing a battery. Or get the code from your service center.

Whilst any problem in the torque circuit is  normally responsible for turning on the EPC light,  the EPC light may also turn on for some other non-emission related engine faults.  When a combination of emission-related and EPC-related fault is encountered, both the MIL and EPC lights may turn on. This alone give one a good idea of whether or not the engine problem is purely torque related or part of an emission-relate issue.

Most pure torque circuit EPC faults are accompanied by Limp-Home Mode which revolve around the basic settings for the Electronic Throttle Control Valve Adjuster, Idling Control, EPC Adaptation and the  Accelerator Pedal Position Senders. Their values are stored in the ECU normally from group 60 - group 62 of the Bosch ME 7 and newer ECUs, however the actual group may vary subject to make, model and engine capacity of the vehicle. For example. Jetta, Polo, Audi TT, etc, EPC adaptation exists at group 060 - group 062, whereas these values may be stored in group 098 for some VW Passat and Audi A4, S4, B5.

Group=060, Adaptation Epc-system
Group=061, Epc-system (1)
Group=062, Epc-system (2)

Emergency Running or Limp-Home Mode

Both Bosch Motronic and Siemens Simos ECU have two emergency running modes to compensate for accelerator pedal sender failure. The first mode triggers when the primary sender G79 (Sender -1) accelerator pedal sender fails, and the second mode triggers when both G79 and G185 (Sender -2- redundant sender) accelerator pedal senders fail. In the first case with one accelerator pedal sender failing, the accelerator position is limited to a predefined value (limp mode) idling speed while some comfort functions will be disabled,  the Air Conditioner for example. By which time EPC light would have already illuminated. However, when the second emergency mode triggers the engine runs only at idle speed. It would be exactly like disconnecting / removing the accelerator pedal completely. On the occasion that I replaced my accelerator pedal, I started the engine and to my surprise it started perfectly normal and idled at a normal rev. So the conclusion is when both accelerator pedal senders / potentiometer fail, it gives you the same, exact, identical symptoms of a physical steel accelerator cable that snapped. Considering a throttle cable is the single most important part of the throttle system in a car engine. So when it breaks the car will idle, but will not rev. The EPC system mimics the pysical cable exactly or as near as dammit.

Siemens Simos ECU J361 with pin connections
Looking at the diagram for accelerator pedal senders G79 and G185, pins 50 and 19 are inputs from their respective highside driver 5V supplies with pins 18 and 45 of the ECU microprocessor are their independent internal earth connections. The two variable voltages at pins 51 and 64 are the inverse of on another. Essentially G185 (secondary) is working as a backup to G79 (primary). Inputs at pins 51 and 64 are constantly monitored by the ECU microprocessor could range from sporadic to too high or too low, to intermittent to absolutely not there. The  ECU microprocessor with its built-in Watchdog Supervision Safety Logic monitoring performing plausability checks for voltage regulation, Over/Under voltage levels, intermittent voltage levels. If for any reason that the calculations based on its internal algorithms do not correspond to its internally stored and expected values either the watchdog processor or the  Main Processing Element enable   a secondary shutdown path to all equipment under its control. In a nutshell, limp mode.

Constant movement of the gold plated contacts on the potentiometer slider eventually wears through and becomes intermittent especially if the vehicle has attained a high millage, considering  how may times the accelerator pedal has been stepped-on and released. It can be roughly compared to a volume control that's gone scratchy from constant use, when it finally worked through its carbon track and makes intermittent contact.  I've known physical  steel throttle cable to last a lot longer than its electronic counter part but they do have a tendency to fray and get stuck inside its sleeve especially when going at high speed, which is kinda dangerous -even life threatening.  With the EPC system this will not happen, rather if the "electronic steel threads fray" the microprocessor shuts the system down by switching over to its stored alternative values.

Looking at the diagram for G188 and G187 it can clearly be seen that they share a common 5v supply (pin 91) and a common earth (pin97) with the outputs from pins 90 and 92 acting as inputs to the ECU microprocessor that control for the throttle valve actuator motor. These inputs are also constantly monitored by the ECU main Processor and its companion watchdog processor. Noting once again that G188 and G187 act as angle sensors much like that of the accelerator position senders. The concept and principal is exactly the same as that for the accelerator potentiometers. When any discrepancy is detected, a shutdown path is enabled which presents itself to the motorist as a car that won't rev. Then there is G61, the knock sensor. Any  knock higher or vibration outside of that expected by the ECU on pin 102 will also enable a shutdown path and sequence limp mode. 

Accelerator 6 pin plug and harness for VW, Golf, Skoda, Fabia, Audi etc.
Accelerator Pedal 6 Pin Plug Connector Wiring Harness for VW, Amarok, Beetle, Eos,
Lupo, Polo,Touareg, Sharan, Transporter, Electronic  - 3B0 972 706
Based on this, the inputs and outputs from these three components are vital to the correct functioning of any Drive-by-Wire vehicle. So when a fault occurs and guided by error codes, it is important to ensure that there is wired continuity between these components and the ECU connector. Wiring harnesses are subjected to a fair amount of shaking and can break inside of the PVC sleeving. Especially sensitive is the 6 pin Electronic Accelerator Pedal Plug Connector Wiring Harness for VW Polo, Golf, Audi, Skoda, Fabia. VW part number - 3B0 972 706. This replacement part needs to be soldered onto the  wiring harness after cutting off the original plug.

Wednesday, October 26, 2016



Electronics have taken the motor industry by storm, so-much-so, that electronic black boxes and discrete components have come to replace several mechanical systems. Case in point - Drive-by-Wire system, where a mechanical cable is replaced by an EPC (Electronic Power Control) system. Or a shared coils and carburetor is replaced by a set of individual electronically controlled coils and electronic injectors. As a result, providing us with increased safety features, tighter and better engine control, additional creature comforts, convenience and so much more. Virtually every system in the modern day car is digitally controlled by a some Electronic control Unit (ECU) or a bank of dedicated on-board computers  distributed throughout the car, all of them networked to a Central Bus System. There are numerous bus systems used in electronics but CAN bus developed by Robert Bosch in 1986, has quickly gained acceptance into the automotive and aerospace industries. With the continued development of more complex ECU applications,  much larger quantities of data needed to be  processed, scores of more signals needed to be measured, and a growing number of other parameters needed to be optimized. 

CAN bus was the answer to surmount these problems though it is essentially a serial bus protocol used to inter connect individual sub systems and sensors as an alternative to conventional multi-wire looms. In a nutshell, cars have gone electronic processors, is firmware based, software driven and data analysed, artificially semi-intelligent and electronically complex.  All of a sudden automotive mechanics needed to learn loads of new words like microprocessor, microcontroller, quantitative analysis, electronic engine-management systems, potentiometers, sensors, signal processing, frequency response, memory-mapped  let alone how their individual functions. To add insult to injury, abbreviations like Controller Area Network (CAN), CPU (central processing Unit), RAM (Random Access Memory), EPROM (Electronically Programmed Read Only Memory), LAN  (Local Area Network), ADC (Analogue to Digital Converter), distributorless ignition system (DIS), etc, just flooded the motor vehicle repair market. 

Talking about abbreviations, EPC, is the official abbreviation for Electronic Power Control when referring to the Drive-by-Wire Torque circuit,  though it also stands for Electronic Pressure Control when referring to the Automatic Transmission.  When the Torque control EPC circuit fails for whatsoever reason, the  EPC Warning Light (K132) located in the instrument cluster lights up, which then could cause the car to enter into "limp mode", depending on the severity of the problem. Limp mode is a protective state that the car's ECU enters into when it recognizes that there is a problem with it's logic program. For example, when an expected signal value originating from a sensor varies significantly from the predetermined program  specification, the ECU then enters into a secondary/ emergency programme in order to protect the engine / transmission from damage. The ECU is constantly expecting a regular stream of signal values from various sensors, like for example the Throttle Position Sensor, or the Mass air Flow Sensor, or the Engine Speed Sensor, or the temperature sensor, etc. As long as these signals stay within specified parameters for certain operating conditions, the ECU performs faultlessly at controlling the engine. 

Due to  the rapid expansion of electronics in motor vehicles, automotive mechanics in general were over whelmed by the introduction of this new evolution in technology and as a consequence didn't stay abreast of automotive electronics, thus now seem to have great difficulty in solving electronic problems on client's cars. Replacing parts indiscriminately with the hope that they get lucky and that the actual faulty component is among the suspected parts that were replaced.  Many, many, many VW, Audi, Skoda, and Seat owners can testify to this, since most have first hand experience of taking their vehicles into the service agent, only to get the car back after having to foot an enormous bill for replacement parts that probably weren't faulty in the first place, only to discover later that the problem the car was taken-in for, still persists.  EPC problems essentially have most VW "mechaicians" by the short and curlys.  But an EPC problem is not that difficult to eliminate if checked systematically instead of trying to trace it by replacing components by substitution.


When the ignition is initially switched on, the Motronic Engine Control Module (ECM) performs a quick self diagnosis of all components that are important for the correct functioning of the Electronic Power Control. If all components pass the  diagnostic test the EPC light goes out. However, should  the Electronic Power Control (EPC) Warning Light not light-up when ignition is switched on, or if a  malfunction  is detected in Electronic Power Control system whilst the engine is idling, the Motronic Engine Control Module (ECM) will turn on the Electronic Power Control (EPC) Warning Light, sort of constantly.  When this happens, a DTC entry is made in the Motronic Engine Control Module, then its time to scan for Diagnostic Trouble  Codes with a scan tool.


EPC also stands Electronic Power Control but also stands for  Efficient Power Conversion (EPC), Emergency Power Cut (EPC), Error Protection Code  (EPC), Event Process Controller (EPC), Embedded Personal Computer (EPC), Embedded Programe Controller (EPC), Erasable Programmable Chip,  Electronic Page Composition (EPC), Editorial Processing Center (EPC), Electronic Publishing Center (EPC), Energy Performance Certificate (EPC), Engineering, Procurement and Construction (EPC), Earnings per Click (EPC), Electronic Pressure Control (EPC), Electronic Product Code  (EPC), Enterprise Planning and Control (EPC), Every Penny Counts (EPC), Earth Population Control (EPC), Enhanced Power Control (EPC), 

....To continue.....