Transponder Key Programming

Since 1994/95 nearly all vehicle manufacturers started to use transponder technology in their cars and keys. Transponders are fitted inside the head of the key. Transponders are small carbon or glass chips which emit data when subjected to a low power electric field. The data (logic) from the transponder is compared to that which is stored inside the immobiliser inside the car. If the data matches, it allows the engine to start. The owner of the car may not be aware that the transponder is there because there are no buttons to press. Programming a key essentially means matching the key's transponder to the immobiliser by use of secure programming procedures and secret codes.

Your transponder does not require a power source. Batteries in keys are usually for other functions such as remote central locking.

If you find your car wont start and it is mechanically fine, you may have a problem with the transponder not communicating with the Engine Control Unit (ECU) or Immobiliser. This may be due to a damaged or faulty transponder. Call us at The Car Key Company Sussex to arrange for us to visit and replace or reprogramm the transponder chip. There may be other problems, but after checking you have enough fuel, and your battery is charged, this is the next thing that needs to be checked.

Without a transponder, your vehicle will simply not start. If it is lost or damaged, the only choice you have is to have another programmed into your car. The Car Key Company are able to do this at the side of the vehicle whilst you wait. In general, the procedure is to put the vehicle's computer into programming mode. The procedure varies between different models, and years. Having put the vehicle into programming mode, most vehicles have a secret code required to access the 'key learning' part of the vehicle's technology. Most garages do not have the tools are access to such data. Having input this secret data, which is available to our engineers, the key can then be successfully matched to the vehicle. In the future, the vehicle remembers this keys unique code and enables the engine to start. Once the transponder has been programmed, we take the vehicle out of programming mode. Job done (after you've paid) !