When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have searched and found similar posts, but nothing specific to the rear door lock which seems impossible to get to.
The rear passenger door won't open from the inside or outside. All the other doors lock/unlock/open fine. It was intermittent last year, I should have fixed it while I had a chance of opening it!
When using the central locking, I can't hear or feel anything happening inside the rear lock, it seems totally dead.
I have removed the rear seats and removed (broken the clips of course) the panel, which is now loose but still attached to the hande/cable and wires. It seems impossible to get access to the lock though the small holes, as the access looks much harder than the front doors.
Does anyone have any advice on how to proceed? I'm totally stuck.
Thanks Dell. I did read that through multiple times before posting but couldn't fathom a proper solution from this. The solution he says was to spend hours trying to grind through the mechanism through the small opening, working blind pretty much. And the opening in the rear door seems a lot smaller than the front doors.. This seems pretty much impossible, I was hoping for another suggestion!
The only other "hail Mary" thing you can electrically try (just in case the actuator can still respond to being manually be driven) is to remove the "B pillar" cover to find the 14 way connector that goes to the door harness.
If it is the RH rear door then it is connector CA30.
If you unplug that you have then isolated the door from the GEM and everything else and can try to feed 12 volts in either orientation to pins 8 and 9.
One polarization will lock the door the other should unlock. (if the actuator is still able to mechanically respond to a voltage being applied).
To identify pins 8 and 9 as they will be black wires from the plug into the door itself, pin 8's wire of the cabin harness side of the plug is White/black stripe, whereas pin 9's wire is a Yellow/black stripe. (assuming your car is 2005 or later).
Just use a 12 volt source.
Note:- Don't use anything higher voltage as the actuator has a voltage spike suppression arrestor incorporated, therefore putting a higher voltage on the actuator may trigger the arrestor to protect the actuator.
Simply use a 12 V battery or a 12v bench power supply that is able to deliver a couple of amps and some leads that you can momentarily touch to the pins 8 and 9 of the door harness - one way will try to lock the door, reversing the leads will try to unlock it.
Hopefully you are lucky and you will unlock the door.
Certainly worth a try before you go all medieval on the thing.
Thanks very much for the detailed reply. It's an 03 and it's the left door.
I'll see if I can remove that panel and find the connector.
You've just given me a thought though, could it be a faulty GEM? I got a spare one a while back due to other very strange electrical faults, but it wasn't needed in the end. I doubt it but it's an easy thing to try swapping out
OK, 2003.....still White/black stripe on pin 8 (14 pin CA25 for LH rear door) and Yellow Black stripe on pin 9.
Now here's a question....is your car "double lock" doors or "single lock" as that makes a difference in the door latch mechanism part number, internal operation and feedback to GEM.
The way to tell is looking at that CA25 plug connector, if you have two Yellow/Black stripe wires (one at pin 9 and one at pin 10) then you have a double lock car which means your rear door latch assemblies have additional microswitches inbuilt to manage the actuator differently.
In that scenario you need to treat pin 8 as the common pin to the actuator and try activating pin 9 and or 10 with your auxiliary 12V voltage source.
GEM is not likely the issue if the RH rear door is still operating as the wiring is in parallel to operate both doors in unison which you can see in the double locking version schematic below.
Integrated microswitches have been problems before and if yours is double locking, then possible an integrated switch has let you down.