EPC DEMYSTIFIED CONTINUED 1

Continued from EPC DEMYSTIFIED.  

  ....But it’s not that simple. There is a lot more to it than meets the eye.....

 PART 2

But it’s not that simple. There is a lot more to it than meets the eye. Cars exclusively use embedded microcontrollers (µContollers) with embedded firmware in preference to microprocessors with loadable software. In order for a microprocessor to function properly in any device, it must contain dedicated internal circuitry and firmware specific to its function, have inputs and outputs and an oscillator circuit among other circuitry and an OS (Operating system). A DVR (Digital Video recorder), or a PVR (personal Video recorder) or a set-top-box or embedded network appliance or data router are just a few examples of such systems. µControllers  are less significant and less sophisticated than microprocessors, more dedicated to its specific need, often cheaper, faster, safer and smaller. Embedded µControllers are therefore the natural choice for car manufacturers. And there are several manufactures that produce µControllers families specifically for the motor trade.

So it should be understood that companies like Bosch, Digifant, Delco  and other engine management ECU manufacturers and electronic module manufacturers uses the same microcontroller chip families or similar microcontroller chip families, designed and manufactured for them by a selected few silicon chip manufacturers.  In the same vein, computer manufacturers like IBM, Dell, Sony, Toshiba and Lenovo, etc. all use microprocessors manufactured by Intel Corporation or AMD in their laptops and computers, whereas Apple uses microprocessors manufactured by Motorola.

Baring in mind, that much like Motorola, Intel Corporation and AMD produces different featured microprocessor chips with different instruction sets,  along with their auxiliary support chips for low-end and high-end computers; such as 4 bit, 8bit, 16bit, 8086 family of chips, 32bit Pentiums, I5, I7, 64bit, XEON, 128bit big Endian and small Endian microprocessors etc; so does Infineon, Altera, Freescale, Atmel and ARM etc, manufacture different featured microcontroller chips for both low-end cars and high-end cars which are specifically chosen for their internal features and software by the various ECU and electronic module manufacturers like  Bosch,  LUCAS, DENSO, Delco, DELPHI, FENIX, HITACHI, HELLA,  MARELLI, Siemens, etc. These microcontroller chip families can roughly be categorized into four sub sectors, those specific to Powertrain functions (P), those specific to the Body and Safety functions (B), those with specific functions for Chassis (C) and those specific to Internal Convenience & communication(U).

In a nutshell all the sub systems in your vehicle are controlled by these on-board computer chips, each at the heart of an electronic module flanked by associated components and sensors. Each of these modules are in fact a fully fledged computer in its own right, situated in various positions throughout the car and linked together by a wired networked called a network bus and all are accessible through the Databus diagnostic interface for adaptation.

When the ignition is switched on, several dashboard warning lamps light-up and stays lit for the duration of the internal test cycle (<30 seconds). Should all tests check OK, all lights goes however if all systems does not check out OK, the relevant light will stay on and a fault will be logged in memory . After the car is started, the ECU monitors all sensors  and continually takes readings from the complete range of powertrain modules and sensors. These readings are then compared with default readings stored in the operational logic of the  system. Should the sensor reading coincide and agree with the stored program value or values, the microcontroller will send the  required outputs to the relevant actuators, for example the injectors. If the sensor readings differ and are out of specification,   "not within the required limits",  it will take another and if this sensor reading continues to be ‘out of limits’ a DTC will be triggered and sent to non-volatile memory. Depending on the nature of the fault, the embedded program may or may not instruct the microcontroller to make internal changes, thus operate on different criteria until a repair is effected, or until the fault has been cleared.

So whenever a mechanical or electronic problem arises in either the Powertrain (P), the Body (B), the Chassis (C) or the internal Conveniences & Communication (U) areas, the relevant module or modules triggers the on-board self diagnostics program and generates a DTC (Diagnostic Trouble Code) which is then stored in the non-volatile memory of the ECU for later retrieval by mechanical technicians. At the point When a DTC code is logged in memory, the system self-diagnosis system also alerts the driver with a visible indication  of trouble by turning on a warning light on the dashboard like the "EPC light", or the "Malfunction Indicator Lamp" (MIL) which on European cars is known as the "Check Engine Light". This doesn't tell you  the nature of the problem, even though it could be something serious, or not. After the necessary repairs are completed, a diagnostic scan tool should be used to clear the DTC errors  and to turn the malfunction indicator light (MIL) or EPC light off. Thereafter the car should be taken on a short test dive to ascertain that the previous drive issue or issues are resolved. Then the car should be hooked up to the diagnostic scan tool once again in order  to confirms that the DTC or DTCs is also no longer present.

The nature of such mechanical problem may  prevent the engine from starting or it may idle erratically, switch off immediately after starting, refuse to rev higher than 1500 rpm and impede driveability (limp mode), difficult cold starting, misfire, lazy acceleration, high idling speed, fluctuating rev counter, excessive fuel consumption, difficult warm starting, excessive black smoke, poor engine response or emits blue/grey smoke,  etc ... Each of these faults and so many others each produce individualized codes.   In most cases it would be expedient to engage the services of a roll-back to get your car to a VW service center so that diagnostics can be run on the car.

With sufficient knowledge and an appropriate diagnostic apparatus (Autoboss, Pico Scope, Range, VCDS, AutoEnginuity,  ScanXLpro), code reader or scanner, plugged into the car's 16 pin diagnostic plug, mechanical minded persons can read these faults, print then or save them to an SD card or harddrive, send signals and communicate with the ECUs, read the measured values and interrogate the actuators. The DTC in memory however do not identify the part that has gone faulty but rather provides you  with a general idea to its area of origin. Often long before a DTC code is generated the fault may already have existed so when the you view the DTC it could show that the fault occurred twice of thrice or even six times before. The ECU software is designed to monitor the frequency of error and if it is an isolated occurrence the ECU clears the fault after a certain distance is traveled but that dependent on the severity of the fault. For arguement's sake lets say 300kms. If it happens once in 300kms it could automatically clears the fault but should it happen four times during the same distance a DTC will be registered, the car could go into limp mode since it may be unsafe to drive the car if it's a breaking or steering issue, or shut the engine off if the O2 sensor went faulty and can't regulate the smoke pollution, or disable starting if the knock sensor triggered the DTC as there may be no oil in sump which could amount to a very expensive engine repair. In the case of the latter, the oil light should have illuminated long before the knock sensor shuts the engine off. However I have encountered a problem with the wires that plug into the oil sensor that became brittle due to engine heat and  subsequently broke off. As a result the sender  sent the low oil condition but it never arrived at the the ECU hence did not turn-on the oil-low light. I only became aware of this when my EPC light went on due to the knock sensor. See picture in blog.   More ...

EPC DEMYSTIFIED

EPC DEMYSTIFIED IN THREE PARTS

PART 1

In a global village where defined lines between languages and nationalities, technologies and terminologies have become completely blurred, it is important to create terms of reference in discussions, so that we are all on the same page but pronunciation can at times offend the ear. To elaborate, some people say "tomarto" (tomato) some say "tomayto", some say micro computer and some say microprocessor, some say Electronic power control (EPC) some say Electronic Pedal control (EPC). But that's just semantics, the bottom line remains, that it establishes a common ground for people of different geographical spaces to discuss common topics.

In response to the hoards of queries I recently received and the abundance of confusion there is out there about EPC (Electronic Power Control); and in reply to the thousands of e-mails I received regarding EPC (Electronic Power Control) that I haven’t been able to reply to as yet nor will ever be able to, I decided to dedicate the next few episodes of my blog to explaining the EPC (Electronic Power Control) problem many VW drivers and VW owners are having with their cars as if they were two year olds. (Not that two year olds can relate the subject at hand).

I have explained EPC in previous blogs, namely EPC light revisited explained and EPC why-engine-light-comes-on, however, I am going to elaborate on the EPC (Electronic Power Control)  concept and demystify it for the benefit of all these people mentioned above and all those destined to encounter this problem at some time or the other. The question is not if you will encounter an EPC problem but rather when you going to encounter an EPC problem, its just a matter of time. Be that as it may, for the sake of simplicity, and by analogy, I'm going to compare the workings of the EPC (Electronic Power Control) in a car to that of a PC (personal Computer) which in my humble opinion will aid understanding.  So here goes....

Electronics as a whole has intrinsically influenced human life globally, especially since the advent of the silicon chip. Through the evolution of said silicon chip, Microprocessors have become so common place, that it finds itself in virtually every modern day technological advancement from computers to televisions, cell phones to cameras, medical equipment to the very cars we drive, to mention but a few. As a result virtually everyone out-there, has heard of, or are familiar with the terms microprocessor, microcomputer or just computer, and as such, it establishes a basis to discuss familiar concepts. Most people in the "Secular World" either owns a computer or uses computers and accordingly have some understanding of its hardware and its software, and how well these complement each other and seamlessly work together. I mentioned this purely in preparation to my assertion that  follows. However, all those non-technical and all-thumbs people and those  who say "you don't have to know how an engine works in order to drive a car", are totally excused.

EPC for Hands-on Dudes, Savvy Ladies and other pragmatic people.
Computers can roughly be subdivided into building blocks, each of which is responsible for a specific function or a collection of functions. As such a combination of these specific functions gives rise to the correct and proper functionality of the computer or computer based device. For instance, the computer hard drive functions as the storage unit that holds the operating system, application programs and user data. The DVD Rom, serial port, keyboard and mouse acts as input devices. Whereas and the speakers, printer & screen act as output devices, doubling-up as the interfaces of information interchange between man and machine (computer). The motherboard houses the CPU (central Processing Unit / Microprocessor chip) it ancillary / auxiliary timing chips, control and data buses, RAM and sub circuitry for  AGP, PCI, MR1, PCMCIA, USB, Ethernet, Fire wire, parallel connectivity, etc. When all these specific components play together nicely, we are guaranteed a fully functional computer and a happy computer user.

Likewise the car can be subdivided into building blocks each responsible for a specific function. In this instance, the engine is the source of propulsion which delivers it to the rest of the drive train. The instrument panel, the steering wheel, the transmission and the braking system constitute some of the input and output devices, also   doubling-up as the interfaces of information interchange between man and machine (car). The electrical system; the ECU (Motronic control unit), Control unit within the dash,  along with its auxiliary modules, oversees the overall timing, sensor, actuator, control and data bus, as well as block components like the Radio, air conditioner and central locking etc. Once again, when all these discrete components play nicely together, we have a perfectly functional car and a happy driver / owner. More...

WHY ENGINE LIGHT COMES ON

EPC LIGHT

Seeing a VW or a Volkswagen or Polo da Volkswagen or a VAG car or a new Polo on tow,  is becoming an all too familiar site, - view picture below. VW cars are seen piggy-backed and carried to service centers on a daily bases because VW owners are encountering serious trouble with their Volkswagen cars.  

Many Volkswagen drivers are often stranded on the high ways or freeways whilst driving to and from work because their VAG cars are throwing tantrums, by going into limp mode and turning on the EPC light.  Most VW drivers have no idea why engine light comes on. 

I've been late for  meetings on several occasions because of this. On a few others, I couldn't make it to the  bank in time because the Electronic Power Control -EPC- circuit incapacitated my VW Polo Classic 2.0L Highline. The worst was when I took my daughter to the dialysis clinic and the Electronic Power Control (EPC) light came on, because I ran over a speed bump a little too fast. This resulting in "Limp Mode" causing my daughter to be substantially late for her dialysis session. This could have been a life or death situation but fortunately it wasn't.

I took this photo with my cell phone. The picture quality really isn't good, so therefore the
Bluemotion badge to the left of the right side tail light  isn't clear at all.  But I couldn't pass-up
the opportunity to capture a VW Bluemotion 2012 loaded on a roll-back.

Anyway,  lets look at why this very risky and inconvenient issue haunts most VAG car owners. All Drive-by-Wire cars (since 2000) has an Electronic Power Control (EPC) light. The EPC dashboard warning lights are not exclusive to VW or VAG cars but affects most other new cars regardless of its manufacturer though the common denominator is Drive-by-Wire and an Engine Control Unit (ECU) often called the Powertrain Control Module (PCM) with an embedded microcontroller supplied by the same manufacturer.  EPC stands for Electronic Power Control which is controlled by the ECU (Engine Control Unit). In essence the Engine Control Unit (ECU) is a microcontroller with associated circuitry which control the sub-modules in the car, all connected together by either OBD II or CAN-Bus. Certain outputs from these sub-modules can activate the Electronic Power Control  circuit, especially if the reason for sending its signals to the ECU (Engine Control Unit)  could cause damage to the engine or is a danger to the passengers. For example, if the car runs out of oil, or if the emissions exceed the prescribed level, or  if  the car hits a speed bump a little to hard or if a brake bulb fails.

In the first case the oil level sensor will detect that the lack of oil in the crankcase and since there is a possibility the engine may seize-up, it sends a pulse train to the PCM to activate the Electronic Power Control (EPC), which cuts the power to the engine, making the car go into "Limp Mode" and switching on the EPC warning light. In the second case the lambda sensors on either side of the catalytic converter  will detect the fuel rich exhaust fumes and send a pulse train to the PCM to activate the Electronic Power Control (EPC), which cuts the power to the engine making the car go into "Limp Mode", thereby limiting carbon pollution and  and switch on the EPC indicator light (epc warning light) . In the third case the engine knock sensors will detect the suspension knock as the car hits the speed bump and will send a pulse train to the PCM to activate the Electronic Power Control (EPC), which cuts the power to the engine making the car go into "Limp Mode" and switch on the EPC dashboard light. In the fourth case, one of the Electronic Control Unit or Body Control Modules (BCM) sensor will sense that a brake light is open-circuit, send a pulse train to the PCM to activate the Electronic Power Control (EPC), which cuts the power to the engine  making the car go into "Limp Mode" because in that condition the car is not roadworthy. The EPC dashboard light is a very graphic demonstration that there is something amiss in you VAG that needs to be remedied.

There are several other sensors strewn throughout the car and many of them can have an effect on the Engine Control Unit (ECU) and cause the EPC light to come on. Sometimes when the EPC fault light comes on, it may be a spurious error, based on past driving cycles. A driving cycle is calculated from the time the engine starts and drives -which should be a min 5 minutes- until the engine is switched off. It could  take three drive cycles to clear a spurious error but if the fault persists it has to be diagnosed on a VAG-COM diagnostic tester.

Should you require more information on,  what is epc light, what is a epc light, vw epc warning light, vw epc code, epc on a vw, epc warning light vw, epc vw tiguan,  epc on jetta, epc light on, what is the epc light,   epc fault light, checkout epc-demystified.

Here are some Non  Volkswagen Websites I highly recommend,  

http://electroniques.blogspot.com

http://photojani.blogspot.com

http://expowp.blogspot.com  

VW ELECTRONIC POWER

EPC LIGHT EXPLAINED

As I mentioned before in my older blogs, the new generation of VW cars are designed to turn on an EPC Light (not check engine light) so that only the  Volkswagen dealership service technician or technicians are supposed to do any an all servicing and repairs.  The VW workshop manuals specifically discourages anyone other than a qualified or trained mechanics / auto-electrician and automotive technician to perform servicing, especially changing codes and performing readiness test.  This is because  incorrectly set readiness and adaptation settings can completely disable your car and virtually render it useless. To repair it would then cost a small fortune.

CHECK ENGINE LIGHT

An earlier blog, covers some late model VAG cars with fuel injection and electronically controlled throttle body instead of the traditional accelerator cable controlling the throttle valve. It is called Drive-by-wire or DBW for short. When the Engine Control Unit -ECU, which invariable is a computer in its own right detects a fault  Diagnostic Trouble Code - DTC  in the Drive-by-wire system, it registers a fault Diagnostic Trouble Code - DTC in its non volatile memory and turns on the EPC light, disables the accelerator and throttle body, limit the engine to a maximum of 1500 rpm -"Limp Mode".  This would be sufficient power to "Limp Mode" the car to a service centre without causing further damage to the car or unduly polluting the air should the fault cause it to smoke. This is a safety precaution and can be equated with, what would happen if  an accelerator cable got stuck in the downward position. Disaster could follow. The Engine Control Unit -ECU collects faults Diagnostic Trouble Code - DTC from all senders and stores an internal list, which is only visible with a diagnostic tester. Diagnostic Trouble Code - DTC can range from excessive emissions to - intermittent air bag connections, from brake light failure to - depleted brake pads, from interior ultrasonic failure to - immobilizer problems to even disconnecting the battery. Each of these faults generates codes, some of which can be viewed in future blogs.

Should the Volkswagen Engine Control Unit -ECU  considered a Diagnostic Trouble Code - DTC to be so serious that it could possibly do harm to the engine or the environment, it will inhibit the throttle function and limit the engine revs or even disable starting or idling completely.  Unfortunately the only way to repair such problems, is to connect the  Volkswagen Golf,  Jetta, VW Polo, or Volkswagen Beetle, to a dignostic tester through its CAN-Bus / OBD2 / OBDII port and view  Diagnostic Trouble Code - DTC  if any and  Diagnostic Trouble Codes, clear them from memory and perform corrective procedures.  Below is an overview of the Electronic Power Control Circuit - EPC and how the Drive-by-wire system operates.

The basic operation of  the Electronic Power Control (EPC) Schematic showing inputs
from drive-train sensors and output signals to drive-train actuators.

Other INput senders could result in similar problems. For example - the Oxygen Sensor could detect that the exhaust fumes carbon mixture exceeds the prescribed level which is toxic to  the atmosphere and the environment. It could disable driving of the vehicle by enabling the Electronic Power Control Circuit - (EPC), turning on the EPC warning light or even disable starting not allowing the car to idle. This could be due to a dead plug causing the idling to be erratic and not burning up all the fuel. This un-burnt fuel will invariably change the exhaust fumes composition which triggered the Catalytic Converter and Oxygen Sensor in the first place.

Like wise, when the brake light bulbs blow or the fuse to the brake circuit blows, an INput signal from the brake light sender could also activate the Electronic Power Control Circuit - (EPC), turning on the EPC warning light causing the car to go into "Limp Mode" because driving a car on a public road without brake lights is an accident just waiting to happen. In fact the Engine Control Unit (ECU) looks upon this car as non-roadworthy as a safety procedure. In a previous blog I described an Electronic Power Control Circuit - (EPC), which switches on the EPC light problem caused by an INput  signal from one of the knock sensors with the same results as above. Other senders INputs that can cause similar problems are:-

The Engine Speed Sender G28 situated at the flywheel.
The Hall Sender G40 situated at camshaft pulley
The Hot Air Mass Meter G70 and intake Air Temperature sender G42 situated near intake manifold.
The Lambda probe G130 situated upstream of catalytic converter
The Lambda probe G39  before catalyst converter
The Knock sensor I - G61 below intake manifold
The Knock sensor II - G66 below intake manifold
The Accelerator Position Senders G79 and G185 embedded in accelerator pedal (EPC Problem)
The Clutch pedal switch F36 situated in the drivers foot well.
The Brake light switch F and brake light switch F47 situated in the drivers foot well.
The Throttle control valve / motor drive assembly  J338 
The Angle Senders  G187 and G188 situated inside throttle body.
The Fuel Pressure Sender -G247

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DRIVE BY WIRE

VW - DRIVE BY WIRE (Drive-by-Wire)

If you arrived on the VW Polo website because you searched for  Drive by Wire (DBW), EPC, or EPC light or engine won't rev, Steer-by-Wire, or limp mode,  then you have certainly arrived at the right place. There are several definitions for ECP, the first of which will be explained, is Electronic Parts Catalog (EPC).

EPC stands for Electronic Parts Catalogue (EPC) and all Audi, Volkswagen,  Skoda and SEAT parts are listed in ETKA V7.2 EPC (Electronic Parts Catalogue). This catalogue is purchasable online and downloadable but the file is huge. Companies like Mercedes Benz, Toyota,  Enigma, Attrakt among many, many others host computer based electronic catalogs of the individual auto parts and accessories that make up their engines, cars, tractors, specialized machinery and farming equipment etc. Restated, an EPC is a catalogue in electronic format much like CVS data or a database file or similar, that can be downloaded or is accessible online.

Then there is the second type of EPC - Electronic Parts Catalog (EPC) software. MultiCat and Msys.EPC are companies that specialize in the software that can display an exploded view of an assembled device. For example, the exploded view of an engine, or gearbox, or cylinder head, showing the individual bolts and nuts, flanges, hoses and brackets, etc. and their component part numbers.

Thirdly, there is also the Electronics Parts Catalog (EPC) which is an electronic list or database of semiconductor components, from diodes to transistors to integrated circuits to thyristors, etc... This EPC is often called and equivalents book or catalog and hosts the specifications of semiconductors from several manufacturers. A typical EPC is the RS Electronic Components and Tools Database. This EPC doubles up as the third type of EPC which is the Electronic Product Code. Component Product Codes look like,  1N4148 or BC337, MCP2515, TYN812RG, etc... for electronic components.

However, there are many more EPC definitions, some of them can be found at the end of this blog. I could explain all of them individually but none has any relevance to the subject at hand, viz EPC - Drive by Wire. Drive-by-Wire also know as  DbW, Steer-by-Wire "x-by-wire" or simply "by-wire".

DRIVE BY WIRE

And finally, the Electronic Power Control (EPC) that freaks out almost each and every VW 1.6 Polo, Audi TT, Skoda, SEAT and  Golf TDI, owner. Most vehicles with Drive by Wire [Drive-by-Wire (throttle control)] usually have a Electronic Power Control (EPC) indicator lights on its dashboard which lights up when  there's a problem with the Drive-by-Wire system. This would involve the two accelerator pedal sensors G79 and G185 and in some cases the two sensors G187, G188 inside throttle control valve body - control actuator. [As discussed in my previous blogs] When the engine idles, neither the Throttle Valve Angle Sensor nor the Accelerator Pedal Position Sensor are monitored for faults by the ECU, as such, the engine does not respond to accelerator input but will limit engine to 1200 RPM.

The  basic components that constitute the Electronic Power Control (EPC) circuit. 

There is no throttle cable involved, because its an electronic throttle control.

The Electronic Power Control (EPC) circuitry consists of EPC light, Accelerator Pedal, Throttle Control Valve,  DBW  (no throttle cable,) Injectors and the Engine Control Unit (ECU). Have a look at the diagram above. The inputs to the ECU is marked green and the outputs from the ECU is marked blue.  Check that the brake light bulbs are OK, if not check the brake fuses. There are other inputs to the ECU from numerous other sensors or units for example the Automatic Gearbox Control unit, Cruise control unit, Air conditioning unit, Lambda Regulation unit, Knock Sensor units, Alternator, Engine Speed Sensor unit, ABS and the  Power-assisted steering unit to mention but  a few. 

The CAN-Bus bidirectional connection is marked in orange. Some of the other inputs like Knock sensors and Lambda regulator and Engine Speed Sensor unit can also cause the EPC light to come on. If the Engine Speed Sensor unit is responsible, it will reset itself after a while and if the Lambda regulation is faulty the vehicle will smoke and turn on both MIL and EPC lights, but if the Drive-by-Wire - DBW (not drive by cable) system is faulty then only the EPC light will be on.

Both the accelerator sensors and the throttle valve sensors work on the same principle since all 4 of them are potentiometers. The input voltage is 5 Volts and the increments are in millivolts implying that there is an  acceleration range of between 0 and 5000.  Throttle valve angle  sensor 1 and Throttle valve angle sensor 2, Accelerator position sensor 1 and Accelerator position sensor 2 sliders makes contact with the resistive track and outputs the appropriate voltage level to the ECU. These resistive tracks are prone to go faulty since they are gold plated contacts running on gold plated copper tracks etched on a PCB. Over time the contacts wears right through the gold and copper plating, only making contact with the bakelite or fibreglass substrate. This type of potentiometers are less reliable than ceramic thick-film potentiometers.

When the EPC warning light goes on and your acceleration goes limp and the engine won't rev-up there is an easy cure but there may be exceptions. Get the car home even if it means driving really slowly in "Limp Mode". Once home, disconnect the battery for about 15 minutes or so, but not more than 20 minutes then reconnect. NB! do not disconnect the Live terminal, disconnect the Earth terminal. If the battery is disconnected for more than 20 mins you will lose your radio settings since the radio also participates in volatile and non-volatile memory of  the CAN-Bus. 

Reconnect the battery but make certain that the ignition is off. Once this is done, turn on the ignition so that the dashboard lights go on but do not start your car and DO NOT touch your accelerator pedal. After about 5 minutes the throttle body will aligns itself. After 10 minutes turn off the ignition, wait for 2 mins then start the car and let it idle for abut 2 minutes as well. By now, the EPC warning light should be off and the engine will rev as normal.You may have to to this twice. If this worked for you, please do give me some feedback with a comment.

VW Airbag diagnostics 

VW Instruments - Immobilizer

   

DON'T FORGET to VISIT

THE PREMIER 

SECURITY EXPO IN
SOUTH AFRICA

VW, SEAT SKODA and AUDI OWNERS  found the following sites interesting.  
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COME MORE EPC DEFINITIONS

EPC - Engineering, Procurement & Contracting, 

EPC - Engineering, Plant  Construction,

EPC - European Paralympic Committee,

EPC - Electronic Product Code, 

EPC - Event Promotional Council,

EPC - Energy Performance Certificate,

EPC - Engineering, Procurement and Construction, 

EPC - Event-driven Process Chain, 

EPC - Evolved Packet Core,

EPC - European Patent Convention,

EPC - Eastern Provincial Council, 

EPC - Electronic Poetry Center, 

EPC - European Policy Centre,

EPC - European Political Community, 

EPC - European Political Cooperation, 

EPC - Evangelical Presbyterian Church 

EPC - Export Promotion Council, 

EPC - Electricity Plant Controller, 

EPC - ElectroPlating Cathode,

EPC - European Payments Council,

EPC - Electronic Packet Collision,

EPC - Electrical Professionals Council,

Etc...,