Help - door locks won't work?
 

.


Hi, this is my first post as a GXP owner! I didn't realize until after I got home that the electric door locks aren't locking the doors. If I use the key FOB or the door switch, I can unlock the doors no problem. But I can't lock them. There is not a click like its trying or anything. It's like it just ignores me. :emb:

The alarm is engaging... and if I set the computer to lock the doors when I put the car in drive, and unlock when I put it back in park, it will unlock the doors like it's supposed to, but not lock them.

Any ideas? The dealership is 6+ hrs away, so I'm not even going to contact them.

Thanks!
Mark

Wow, never heard of anything like that, I supose if you can get a print of the door lock circuit it will inevitably lead to the BCM, but you would have to trace it out, try a Chiltons, Haynes, or go to AllData.

Probably has to do with that "feature" that makes it harder to lock your keys in.

Try disconnecting the battery for awhile and see if it resets whatever is messed up.

I have the same thing going on with my drivers rear door. I just noticed last nite that it will not lock by remote. But it does unlock

I'll try a computer re-set tonight and see if that gets any results. Thanks!

Well, a battery re-set didn't fix it. Looks like I get to track a wiring issue!!!:bang: I hate wiring!

Wonder if theres a way to test the bcm... might be more than a backyard mechanic can handle. Theres a couple hundred down the tubes.

Probably a dumb, "duh"-type question, but is the car still under warranty?

Yea, if it's still under warranty this is something I wouldn't even feel like dealing with myself.

Negative on the warranty... it was sold "as is".

I guess I'll start with the fuse box... I can't imagine the "unlock" mechanism being on a seperate circuit as the "locks"... but it's a start! :confused:

Are all of the fuses in one panel on these cars? I know on some brands they'll have 2 or more fuse panels.

BTW... I tried a search but didn't see where the BCM is located on these cars. Does anyone know? I'll trace everything between teh BCM and locks.

I'm not an electrical wizard.. help me out.

Do you have one relay for the unlock and another for the locks?? The BCM must hold the relay (or relays)... when unlocking I hear a click from the BCM... but I don't hear anything when trying to lock. This is driving me nuts!! :punch:

I took the BCM apart, there are two relays in there (soldered into the board)... but without a schematic I don't know what they're for.

Help?:emb::emb:

On a side note, I know I'm getting a constant 8VDC at the switch, and the switch makes contact (continuity), so I feel like the wiring is OK...

Mark

Just order a bcm from a auto store that allows returns.

fuse might have went bad. they first time i hookd up the hp tuners it blew a fuse. then none of the electric worked: windows, dash gauges, etc. what was weird is that i couldn't turn the key manually to lock/unlock the doors so i had to keep it unlocked. now that i fixed the fuse, i can manually lock/unlock the doors again. maybe it was just a coincidence but you could check all the fuses under the hood

It is the BCM...
 

Not the switches as it doesn't explain no Lock using fob. And it's very unlikely that the lock on both switches and fob have failed together. With the fob, only the bcm outputs lock/unlock. And I would figure that if the DIC is set for door locking when shifting out of Park, it isn't locking either.

Power and wiring to the door lock motors if probably fine as they do unlock since lock is just the current flowing in the opposite direction.

There is no documentation in the service manual on the internal guts of the bcm and I've never seen the insides. If you can trace the inside wiring that go to connector C2 pins 46 TaN-driver door only; 51 TaN-the other doors; 52 GreY-door locking -- maybe you can figure something out to try fixing.

Otherwise a replacement BCM which according to the manual must be programmed with a scan tool is required. Maybe(??) a used bcm from a GP with the similar options could work without re-programming.

Well, I caved yesterday and took it to the local dealership... we'll see what the damages are later today.

Let me know. Now none of my doors will lock and only the drivers door will unlock. I had a warning about a theft attempt right before they stopped working.

I just got the call... the BCM is the culprit. ~$385 + $200 programming fee.

Plus he "recommended" I have my brakes replaced for the low low price of $1,200. :eyes:

Screw that... I'm going to pull the BCM apart tonight and see if I can replace the relay on the board. I'll have to find a replacement part, but I'll see what I can do.

If it works, I'll take pics and let you know!

Mark

Well hate too see that kinda price, and I also hate too say I told you so, so I won't. Look on ebay local salvage yards, and what ever else you can think of, for the BCM also $200 for programing is outrageous!!!! $75 tops! Also, brakes, what are they quoting you for? Discs and pads for all 4 corners? if so, well, thats still high for me. Look online, there are much better products than OEM.


Edit!!

If you can pull that BCM apart and find the problem, please post how you did so.

$1200? I'll do them for $1,000 and even buy you dinner before I do them!

Buff pointed out something last winter - check your door lock cylinders while you're at it. Mine's frozen solid - rust eater in it for 3 months and still nothing!!!

Hate to have my fob stop working - I'll never get in the car!