Re: Key Code Query
I had the same problem after immediately after disturbing the relays on the battery compartment. The relays are in a bad position with the poor weather proofing so I examined the terminals and they were corroded, therefore increasing the resistance. After having cleaned them thoroughly with my wife's nail emery board, I disconnected the battery. I topped up the battery and ensured full charge. I reconnected everything and it was fine. An immediate sigh of relief given that I am pretty much not going to spend too much money on the car now that I am off to Oz. As for these units forgetting the code, this would be a rare as the codes are embedded in the cprom chips in the ecu. If the code light comes up with the right key inserted it is more likely that there is incorrect resistance in the circuit. The ecus are designed to work within certain resistances in the circuits to cope with different temperatures etc, but corroded terminals or high resistance across a wire can be outside the range of these values and the circuit logic will fail.
145 1.8TS 16v (2001)