Sorry- another central locking fault question.....

Post Sun Mar 20, 2016 8:37 pm

Guys

My Son's recently bought 4 door has next to no central locking. I see that there are many posts concerning this but rather than tag on to someone elses, I thought it best to start a new one.

Symptoms:

Nothing responds to the key in the drivers door (But there is a relay click from the vicinity of the control unit.)

On turning the key in the passenger door, the boot will lock, but not unlock-that is all.

The fuel filler actuator has been removed.

I have read the WIKI as well as previous posts on the subject. I have carried out the red/black wire mod (Which had already been attempted but badly.) I have removed the control unit and examined it-the thermal cutout is still soldered and there are no obvious signs of damage-there are no signs of water ingress. Nothing I've done has made any difference.
I saw in another post that Brian Mooore suggested activating the CL by shorting the wires in the plug to the control unit-tried as suggested and the symptoms are exactly the same-no change.

All four door latches seem very free-no sticking etc. Wiring to each door seems intact.

What should I try next?

Many thanks.

Post Sun Mar 20, 2016 9:06 pm

Disconnect all the lock motors, except one, and try that with the wire links in the ECU plug. Unplug that lock motor, plug in one of the others and try the wire links for that one. Repeat until you have identified any defective motors.
Only connect the second wire link momentarily (about half a second max.) or you will cook the good motors.
Once you have a full set of working lock motors in place, we move on to the control circuits.....

Post Tue Mar 22, 2016 2:01 pm

Thanks for that. It might be a while until I can look into this-I live near Birmingham and my Son lives in Huddersfield. (He isn't mechanically confident yet.)
Will report back once I get chance to test as suggested.

Post Fri Mar 25, 2016 4:43 pm

Well, he came home this weekend so had a look. The reason the central locking isn't working is because all 4 door actuator motors are missing......

So once I've managed to source some, I can then start the testing......

Post Fri Mar 25, 2016 7:42 pm

Not a very late car with the lock motors built into the latches, is it?

Post Mon Aug 08, 2016 4:13 pm

Only just noticed this reply-sorry Brian!
No, it's a 1990 4 door and the actuators were all missing-wiring plugs and link rods there though.
Strangely enough, he's coming home tomorrow, I have obtained a set of lock motors and I'm going to be installing and testing them over the next few days. Will report back with how I get on.....

Post Wed Aug 10, 2016 4:48 pm

Just to feed back for future use. You'll remember that this 4 door saloon had no door actuators at all. I got a set and fitted them-all works as it should. Turned out the boot actuator that wouldn't work was actually a door one. Fitted a correct one and that's working too.
Just need a fuel flap actuator now as that was seized.
Will probably never know why someone just removed all the actuators in the first place!!