Central Locking issue Advice Please

[YodaTdi]

Hi All.

2006 Fabia Tdi.

Recently car locks itself when opening or closing the n/s front door (has done it on the o/s front before too).

Now, it even locks itself when I'm driving down the road.

It will open up if I use the inner door button or key fob but I have been locked out when Ive forgotten to take the keys with me when exiting the car!

Local garage found a wire had "chaffed" & re-soldered it & seemed ok for a while but surely this can't be just a loose/frayed wire if this happens when driving along too & not opening the door.

Apparently this wouldnt show up on a fault reader & cant afford "trial & error" fixing.

Any help would be awesome!

Thanks folks 👍

[Breezy_Pete]

Experiment repeatedly (to try to build up a clear picture) with each of the front doors as follows:

 

Unlock the car with the remote fob, open just one of the front doors and leave it open for a minute without doing anything else. If the car remains unlocked then the 'door open' message has got through to the places it needs to. If the car re-locks itself automatically, then it hasn't sensed that that door has opened. This points to an issue with the lock unit, usually. Sometimes it's the microswitch on the outside of the lock unit, sometimes it's a cracked solder joint, sometimes a wire broken; either way, replacing the whole lock unit is the pragmatic fix. 

 

It may be that you don't get a 100% pass/fail situation for each of the doors - both microswitch and solder joint problems can present as intermittent issues - but it may clarify which is currently the least reliable, and then probably worth fixing that one, and repeat testing of the other side if any misbehaviour remains afterwards.

 

If you have an electrical test meter and want to test the wiring yourself, you can unplug the light brown connector where the door loom connects into the A-pillar, and measure between pins 2 and 5. These should be short-circuit/connected while the door is open. This is only goin to prove that the wiring is intact if you ever get a positive result. If you never see that short circuit, it could be the wiring or the lock unit at fault.  Realistically, a visual inspection of the wires in the door hinge area each side will tell you if there are broken ones; the thin brown/yellow (UK pass side) and brown/violet (UK driver's side) going to pin 2 of each of the light brown  A-pillar connectors are the most likely culprits.

 

 

 

Edited 26 August, 2021 by Wino

[Breezy_Pete]

Our Fabia developed very similar sounding problems to yours, and it turned out to be a failed solder joint within the passenger front lock unit:

Locking misbehaviour, another possible cause - Skoda Fabia Mk I - BRISKODA