I have a 2009 bmw 528xi which needs a engine computer. They are on the internet to buy for less than 200. A new one is over 1200. However, no one seems to know how to program and flash it to the vehicle. They say you can not put a used one in because it does not match the vin on your car. Can you shed come light on this for me. Why do they sell used ones then?
For the E60 platform, there are 3 pieces locked to each other:
- The DME (engine computer)
- The CAS module (Car access system i.e. anti-theft)
- the Key Fob
The DME and CAS both have an ISN (serial number) encoded to them during installation. When the key is inserted, the CAS queries the key then the DME to make sure the DME matches. If not, the CAS does not allow the start solenoid to be activated and the DME will not enable the starting routine of injectors, ignition, etc.
A used DME and CAS may be paired if not already matching, but this is beyond dealerships ability and requires use of aftermarket (gray market) software. From the dealership's perspective, a new CAS and DME must be purchased together and come from BMW AG pre-paired.
Keys are the other problem, the CAS must be programmed to accept the Keys. This can be done at the dealership for new keys (uncertain on used keys).
After (gray) market software (AK300) allows reading and writing of Keys to the CAS, but there aren't many people out there advertising (for obvious reasons) how to do so.
If you are truly in need of a new DME, your best bet is to get a full set of DME, CAS, and keys. The CAS and DME can then be programmed using WinKFP (with UIF write enabled) to program your car's VIN into them. At that point the only thing that will be mismatched is the KOMBI module (gage cluster) odometer reading to the CAS/DME odometer reading. That's another obstacle to overcome.