This applies to MY2000 fabia comfort. Sorry for the lengthy post.

Last winter I found that after particularly cold nights, the remote central locking wouldn't unlock properly in the morning (I could hear the motor whirring once instead of the usual twice but the door remained locked, I could enter the car normally using the key) Later each day, when it had warmed up a bit everything returned to normal.

This problem has steadily got worse, recently it has been happening every morning - but again it would return to normal later each day.

Now each morning, during the period when the locks don't work:

- the red lights in the doors randomly flash on and off, regardless of which door is open;

- the locking / unlocking switch on the driver's door works intermittently;

- sometimes the locks go crazy locking and unlocking by themself, one time it deadlocked me inside.

If I pull out fuse 49, I can lock the car manually, but rather oddly the electric window controls reverse in this condition, and the boot remains permanently unlocked - so I don't appear to have the option of reverting to manual control.

I have examined the circuit diagrams, and it all seems to work on a CAN bus system, and the functions or control seem to be shared somehow between the convenience unit 6Q0 959 433A and the Onboard Power Supply Control Unit.

Can someone help me to identify which of the control units is likely to be failing? I have an Autel VAG405 code reader but it finds no fault codes.

Thanks

Andy

convenience unit 6Q0 959 433A is the most likely culprit.

convenience unit 6Q0 959 433A is the most likely culprit.

Thanks for that.

Do you also happen to know if a replacement must be the same exact part number? I see some on ebay with different suffix.

Thanks

Edited 9 August, 201114 yr by bnjyn