Central locking problem

[jiwilson]

I have a obscure central locking problem. It occurs intermittently and I cannot detect any pattern.

Mostly the remote central locking works as it should. All doors lock and mirrors wind in, indicators flash as they should. The anti theft arms correctly.

But, occasionally, only the nearside doors and the boot locks. The anti theft arms correctly.
However the offside doors do not lock and the mirrors do not move.

If I leave the car to stand, do nothing to it, the functionality mysteriously returns.

Anyone got any idea of where I start???

Thanks in advance.

Ian Wilson
__________________

[Tatsfield]

The off side drivers door has all the controls that activate the other doors. I'm not sure about Volvos but on some other makes it is possible for cabling in the flexible conduit between the drivers door and the frame to lose flexibility in the insulation which cracks and puts shear stresses on the copper conductors within. Movement of the door can cause breaks in the circuit which return when the cable is left at rest. Other variables like temperature and how often you open and close the door can also contribute. I'm not saying this is the cause but it might be a starting point to examine the condition of the cables coming out of the drivers door.

[jiwilson]

Progress.

As advised I have read the codes via DICE. The DDM was showing as unresponsive.

Took outer door card off. Disconnected two connectors to the DDM. Cleaned the contacts and re-assembled. Also "wiggled" the harness a bit. Didn't remove inner door card so no access to main harness where it leaves the door.

Put every thing back together, and it worked OK!

Seems DDM is functional which is just as well because Volvo quoted me £250 (inc VAT) and it needs coding to the car!!

Although central locking is now working the full down, full up function on the drivers windows has stopped working. Window still winds OK but "manual".

Now a awaiting game to see if problem returns....

Watch this space.

Thanks again for the replies - seems so obvious when someone else points it out to you.

[jiwilson]

BTW.

DDM only operates on offside of car. Near side has its own module.

[Waynedance]

Did you reset the windows ? I believe on most cars you put the window to the top and hold the switch up for a time.

[jiwilson]

I understand it's possible to reset windows via VIDA. However I'm still struggling to find that function. Can anyone give me a lead?

[jiwilson]

Issue has returned, in fact its never gone away.

Traced whole of harness behind door card, found nothing.

Removed and cleaned switch timber in DDM. no change.

Been quoted £156 for new door harness.

I have been advised by a trusted independent that the problem will be in the harness where it enters the door. Thats behind the inner cover and i haven't been there yet. That's my next stop.