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Auto Electrics & vehicle Diagnostics in Tunbridge Wells and Surrounding Area 07944186458
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Vehicle elctronics

Diagnostics and component testing 

How OBDII Works All modern cars have an on board computer system that keeps it in check and highlights problems to the driver. This computer system constantly receives information from sensors in the engine and adjusts the system settings so the car can run smoothly. When a problem is detected the computer cannot fix itself so it triggers a warning to the driver. A technician can use a diagnostic scanner or OBD equipment to more accurately identify a potential problem area and resolve the engine fault. The system also produces a code that can be used to help identify the area and nature of the problem. With the right equipment running a car diagnostic is a straightforward process as many cars have an On Board Diagnostics computers. This interface allows me to use generic tools or scanners to identify problems on virtually all makes and models of cars. The computer scanner is inserted into the interface connector and once the car's model, vehicle identification number (VIN) and engine type is entered into the scanner the diagnostic codes can be accessed. It is these codes that helps me know where to start looking to find the problem. Not all ELM lights on will cause a running problem and may remain on for years without undue concern, if for example there is poor starting , excessive fuel consumption , poor running or idle conditions then perhaps its time to plug in a OBD device and see what is going on. If your car appears to running fine and the fuel economy is not really high and money is tight sometimes you can just leave the light and ignore it. When they say industry standard communication that doesn’t mean all cars and all systems, often vehicle manufacturers use specific diagnostics equipment  which will be needed to run certain tests and operate actuators , run pumps and monitor sensors,  many manufacturers have these systems in the dealership only…. Peugeot  have the Peugeot planet Citroen have the Lexia interface Volvo have  the Vida system Vauxhall use  OPcom VW group use VAG com Ford have  IDS Land-rover use JLR Mongoose system Toyota use GTS Fiat use MultiECUScan Jaguar use IDS or JLR Mercedes Benz STAR Most garages will have a generic diagnostics interface from suppliers such as Snap on Mac tool Autel, Bosch which are sold with subscription to garages which you can buy but the ongoing expense would be a unnecessary burden for most end users. So there is a large market for cheaper interfaces such as ELM327 which if Blue-tooth enabled can be linked to your mobile phone they lack activations such as running pressure pumps or release VW electronic brakes, but will aid in fault finding. Ebay and Google have listings for various system such as Autocom CDP , Delphi , Autel  or Wurths WOW software only thing you will need with some of these devices is a basic laptop, generally these are illegal clones. So what does the scanner tell me about my problems here is an example of a diagnostics of a customers car  view document what we can see is some anomalies, first thing to recognise is not all fault codes are important as some are stored in the memory unless they are deleted for eg low voltage across various system, well if the battery has been flat at some point then the system will store this as a fault until its deleted, perhaps you have a problem and decide to start unplugging component with the ignition on these will flag as faults same goes for some other component ABS sensors. Best advice is take a note of everything that is throwing up a fault then simple delete all fault codes and rerun the system after an ignition off and restart or turn over engine, then see what reappears , this is were the relevant info comes in.