Hello all!

88 xj6: Trying to diagnose an issue with the central locking that is making me crazy!

First the problem: The doors, trunk, and gas door will not lock or unlock with the key, or the button on the dash. The windows will roll up when you push all the lock knobs down by hand or turn the last one with the key.

What I have tried so far: Traced all the wiring, everything seems to be getting a good signal, I have a signal from the microswitches in both front doors, power and ground to the central locking ecu, I took the drivers side actuater out of the door and inspected it, it looks to be in good shape, no visable water damage. I also tried a second central locking ecu from coverty west with no change. I tried all the procedures I have read here for re-syncing the locks with no luck. Yesterday I was testing the microswitches in the drivers door (everything tested good), after getting frustrated I decided to put the original ECU back in...turned the key in the passanger door and EVERYTHING worked...4 times, I walked away from the car, didnt touch a thing, came back to try it again and now nothing works again. The last thing I tested was power to the actuaters, I can see a change in state when I turn the key in the door but it only sends 0.008 V which Im sure is not the way its supposed to be, can someone PLEASE help me shed some light on this problem?!

thanks for reading my long first post

 

Does the key work in the passenger side drivers door when the unit is back together in the car?

 

no, i havent gotten it to work again at all since the time right after i switched units back....i even tried tricking the doors by manually closing the latches so i could get to the actuators with the door physically open....i hear clicking all around the car but nothing moves

 

I think it was both JTO and PoBoy that told me to look for a stuck actuator a couple of years ago.

They were correct.

 

how did you cure it? just manually move them up and down a few times whilst spraying lube in them or something? a parts guy i talked to said its almost impossible to find the 88 actuators anymore??

 

Well unless I am mistaken an actuator from any XJ40 will do, although you may have to change the wiring connector (I did).

Also the actuators can be swapped over from side to side it is just a pig of a job to remove them from their holding frame then turn them around. The screws are rock solid.

I found that disconecting one by one and trying to lock/unlock helped me find the bad one. I also found it easier to remove the control rods from the actuator before testing, these can jam in the door causing the actuator not to move.

This is the thread I had Central Locking Problem. OK we went a little off topic, but still.

 

went around and disconnected all the actuators in the doors one at a time and it made no difference at all...when the key is on i hear click....click.....click....click.....click,click when pushing the panic lock button....it sounds like i get the same series of sounds when the key is in the door as well but its hard to tell from outside the vehicle

 

ok another update...if i remove the locking module and ground purple/orange and power purple/pink (or vise versa) all the actuators work!! with the exception of the gas door but i unplugged that to leave it out of the system, however i still can not get either door or the central button to do anything other than send clicks through out the car. Every wire going into the module is getting a signal that i can watch change...what am i missing?? i dont think it is all that likely that i have 2 central locking modules here that are both bad