2015 CX-5 Passenger Door Lock Issues

[onHold]

So I've had a few issues with all 3 passenger doors that has evolved over some time. Biggest issue is now my Front Passenger Door won't unlock either with fob or manually from inside. Rear RH will sometimes respond to fob unlock, responds to fob lock, and it will unlock from inside. Rear LH won't respond to fob at all but it will lock/unlock from inside. Driver door works as normal.

I believe these problems originated from what ultimately became a battery failure and replacement but can't be sure. I had to replace my Front BCM due to this battery failure to fix an issue but, as far as I understand, the Front BCM has no role with locking.

The Rear BCM does play a role though and it makes sense that it's a singular problem with all 3 passenger doors impacted in some way.

When running Rear BCM Test I'm getting B1174 DTC - Passenger Door Interior Unlock Switch - 11 Circuit Short to Ground.

Following my experience with the Front BCM, I tried replacing the Rear BCM but this didn't change the dial but it did move the DTC from B1174:11 to :13 which is Door Lock-Link Dwitch Unlock circuit malfunction.

Thanks for getting this far.

Does anyone have a gut on where to go next?

More Rear BCM investigation? I'd ideally go to the front passenger door, remove the trim and test the lock link and actuator but I don't see how I can remove the trim if I can't open the door - has anyone tried this before with a locked door?

Any help would be great.

 

[stickerbush]

Do you have a fresh name brand (Duracell etc) battery in your fob?

 

[onHold]

Do you have a fresh name brand (Duracell etc) battery in your fob?

Yes I did change battery. Since one lock isn’t responding at all from inside the car, I think there has to be an electric short of some kind.

 

[kdaug]

I had a somewhat similar problem happen years ago, but I can't remember if the problem was non functioning door locks and/or windows. It may have been in a gen1 CX-5. I read on a forum that the issue was often caused by a loose wiring connection in the door that leads to the door/window switches. I took parts of the drivers door panel off to access the switch connections and low and behold there was indeed a loose connection. I plugged it back in and the problem was solved.

 

[onHold]

I had a somewhat similar problem happen years ago, but I can't remember if the problem was non functioning door locks and/or windows. It may have been in a gen1 CX-5. I read on a forum that the issue was often caused by a loose wiring connection in the door that leads to the door/window switches. I took parts of the drivers door panel off to access the switch connections and low and behold there was indeed a loose connection. I plugged it back in and the problem was solved.

Thanks - you had to do this for each impacted door I assume - or 1 door fixed all?

 

[Mazdiod2]

If it seems too difficult to remove the passenger door panel maybe start with the driver's door panel, maybe it has some control over the others. Does the child protection apparatus affect just the passenger doors?

 

[madar]

I had a somewhat similar problem happen years ago, but I can't remember if the problem was non functioning door locks and/or windows. It may have been in a gen1 CX-5. I read on a forum that the issue was often caused by a loose wiring connection in the door that leads to the door/window switches. I took parts of the drivers door panel off to access the switch connections and low and behold there was indeed a loose connection. I plugged it back in and the problem was solved.

This seems like a good place to start. I've had an issue with all 4 locks firing repeatedly on occasion since new. Dealer pegged it as a "can't replicate problem" even after I showed them a video and it happened on their lot in front of the service advisor when picking up the car. Anyway, problem seems to be related to the door handle/lock mechanism in the drivers door. Maybe one of these days after 10 years I'll have a look. Check the connections, maybe squirt a little electronic cleaner in there. I seem to remember some kind of TSB where water might get in there affecting the main switch in the drivers door.

 

[onHold]

Thanks for the responses. I've still not taken a look further yet. Will

If it seems too difficult to remove the passenger door panel maybe start with the driver's door panel, maybe it has some control over the others. Does the child protection apparatus affect just the passenger doors?

Child protection is a manual switch in the door frame. This does work normally - well as far as my doors are normal. Rear doors only.

 

[onHold]

Thanks for the responses. I've not progressed this yet but will update when I have more.