How frequent a problem are the failure of motor driven door

[Martec]

Today I went to see a local electronics engineer who had agreed to have a look at my spare S type rear door lock (my stepdaughter paid back a few favours). It took me almost a month to find the original submicroswitch and he has found two possible alternative replacement switches to try for a repair.

I'm trying to find out if our's and Roger's spare car (where the spare lock came from) were unfortunate or is this a very common problem. I am interested in the motor driven locks, not the solenoid locks, so assume that they were fitted across ALL the ranges at least from 1998 as they will probably have these submicroswitches in them.

Have you had one of these locks fail?

Jack (electronics engineer) seems to think that although these switches are supposed to be good for half a million switchings, if the motor draws extra current then it will burn the fancy metal off the switch contacts and so they fail. I have found corrosion on the linkage inside the lock that could cause this, so will be looking to oil the linkages if possible (impossible access from the inside of the door).

So please can you let me know how common or not this problem is?

Brian

[J44EAG]

I have a reluctant drivers door lock which won`t unlock when the journey is finished. However it does respond to the key fob.

Rather a different problem I think.

Other than that no real problems with door locks in eight years across two cars.

Mike

[Martec]

Both rear door locks now only work manually, its like the rear door locking on the MkII!!

Brian

[J44EAG]

Sounds like a control module problem, Brian.

Perhaps try to get the module box open for a look inside. Plugs and sockets can also corrode with a vengeance

Mike.

[Martec]

I went up to see Jack Franks [jack@optocam.co.uk] about the spare door lock and he has managed to get some submicro switches and the door closed switch (I trod on it!) and soldered it all in place. We tested it on the bench and all was well.

Today I took the door card off again ('somebodies draws' comes to mind!) and connected the spare lock to the car, it worked perfectly. Now I have to work out how to remove and refit it without dismantling the door.

The opposite rear door lock is playing up but I will check the wiring for breaks first.

Brian

[dg4cars]

I have a reluctant drivers door lock which won`t unlock when the journey is finished. However it does respond to the key fob.

Rather a different problem I think.

Other than that no real problems with door locks in eight years across two cars.

Mike

Interesting, my drivers door look has developed a similar intermittent proble. Usually the key fob sorts the problem, however on one occasion, thankfully while the car was on my driveway I had to climb out across the passenger seat. Not a pretty sight! :

[Martec]

I am becoming a very sad git, I've just looked at the door locking system again, the passenger and both rear door locks are all controlled via the RECM, but the drivers door is completely separate, it is made up of the keyless entry unit, then the drivers door lock module and then the door lock, and all controlled via the CAN bus or similar protocol system (I must get out more).

From a chat with an RAC man, he had been called to an S type and found that the drivers door is the only that can be opened with a key under any condition!!! apparently a requirement of somebody. Also after 2005 or so door will automatically double lock after a set time regardless of what you set them to.

Assuming I can eventually recon my door locks, I will file off the tags that double lock the doors, similarly I don't have locking wheel nuts (the car isn't worth much) and ease of access is more important.

Corrosion on part of the latch mechanism could well be the main problem with these locks, but its getting to it to lubricate it as it is near the rear window runner inside the door!!

Best of luck
Brian