Hello, I am a new owner of a second hand 2002 C3. Problems....! When the car was purchased the dealer informed me it had recently had a new battery fitted and it had be "reprogrammed" to the ECU. after a couple of days the key (only key I have) with remote would not unlock the door. Also once unlocked manually the car would not start, the starter motor turns over but the engine would not start. After disconnecting the battery and reconnecting it immediately the doors opened with the remote and the engine started perfectly... Over the last 2 months this has been a fairly frequent occurrence. Sometimes after the car has not been used for a week it opens and starts other times the day after being used it wont't. Very frustrating. Does anyone have any ideas? Thanks in advance.