Woke up one morning and all the locks—except the driver door—suddenly stopped responding. Cargo door, rear passenger doors and front passenger door, all of the locks can only be manually locked or unlocked.

Key in the driver's door both locks and unlocks the driver's door, and the central locking button also locks and unlocks the driver's door, but only the driver's door. Not even an attempt at movement on any of the other locks so it's not like four of the actuators suddenly got weak or gave out—they're not even trying.

It rained hard the night the locks went out, and some severe windshield leaks—which I've since dealt with—were spilling water inside, so that may have done something. I don't know, corrosion on a ground somewhere?

I've just replaced the passenger compartment fuse box entirely with a clean unit, to sort out some other electrical issues, but didn't have any effect on the locks.

Any ideas?

 

let it dry out and test again in a few days

 

It’s been about a month.

 

I'll add that I tried a "force unlock" and "force lock" command on the actuators from the Lynx diagnostic system, to no avail. Same as the CDL button, only the driver's door lock responded, so it's like there's no communication being sent to the other locks. BCU?

 

try looking at fuses relays etc, dig up the rave manual for electrical section and take your time, these things are never easy unless your a eletrical car wizard

 

I have recently spent time digging thru the internal fusebox wiring to solve my central lock issue. I had a bad relay which prevented the unlock function on each door.

Not sure what your specific failure is, but I do know there are 4 relays that control the lock and unlock functions. The drivers door is a separate relay which may explain why it works differently.

I found the lock control wires at the fuse box connector and manually tested the doors to verify the door hardware was ok. I jumpered 12v and ground direct to check the actuators.

 

Thanks for the idea AKJOHN, but I'm not seeing any relays mentioned in the wiring diagram related to Central Locking? Am I missing something?

 

Here is a diagram of the relays. They are controlled by the IDM (intelligent driver module). Where are all of the intelligent drivers when you need one ? Ha!

It is possible to pull the connectors from the fuse block and carefully test each door actuator manually. I did this with mine and found the doors worked perfect. So my problem was with the relay control. In my case, the unlock relay was stuck.

Fuse block relay schematic