Power door locks won't unlock three doors.

[Roadmonster]

Hi guys.

Just joined the forum, and did some searching before making this post.

My wife drives a '99 Yukon Denali, that we bought about six months ago. She is in love with this thing!

It is completely stock. No aftermarket stereo or alarm.

Last month, the door locks stopped unlocking the front pass door, and the rear driver's and pass side doors. The Drivers door, and the rear "barn doors" still do unlock.

It doesn't matter if you use the remote or the Drivers door switch.

Also, ALL the doors will lock with the remote or the button on the door.

I can't figure out why those three doors won't unlock

I did buy a set of switch panels for both front doors, as I got them for a great deal, and I knew that down the road I could use them for spare parts as switches break (my wife says she will NEVER get rid of her Denali).

Swapping out the switch panels and all switches made no difference.

So, here I am...

Any suggestions?

Also, I am going to pick up factory service manuals, just haven't done it yet.

Thanks in advance for any help!

Stewart

 

[Roadmonster]

I'll be taking the Denali in to a mechanic, as I can't figure this problem out.

I'll post the outcome here so maybe someone else who has this problem can fix it themselves.

Stewart

 

[Richard]

anyone have an answer to this? mine started doing the same thing

 

[JKmotorsports]

Actuators are more than likely getting weak. There is less strain when the motors are locking rather than unlocking because of the latching mechanism, which could explain why it locks but doesn't unlock. I have customers come in with the exact same problem all the time and I end up replacing the actuators with new ones.

 

[Richard]

I took the truck to my GM dealer and here is what they did for the fix:

"B RH SEAT/POWER WINDOWS AND LOCKS ARE NOT WORKING - DIAG AND ADVISE (PASS FRT SEAT AND PASS FRT DOOR)

EM11 SCAN TEST AND INITIAL DIAGNOSIS. RECORD TEST RESULTS. REPROGRAMING MODULES, KEYS AND KEY FOBS EXTRA IF REQUIRED .5

REPROGRAM POWER DOOR MODULE .8

182138 THE PASS DOOR MODULE HAD LOCKED UP. MODULE BEGAN WORKING PROPERLY AFTER REMOVING PDM FUSE FOR A FEW SECONDS. FOUND NEW PROGRAMMING FOR THE PDM LOCKING UP. REPROGRAMMED THE PDM AND NOW ALL FUNCTIONS ON PASS SIDE ARE WORKING."

You need a GM scan tool to do this - they are about 3 grand. Unless someone can give me an idea of how to get my hands on a scan tool for a WHOLE lot less - this problem is not for the "do-it-yourselfer".

BTW - I did a bunch of research on the net - GM is aware of the lock-up problem with the passenger doors on these vehicle - just as they are with the intermediate steering shaft issue. Way to go GM! Why not just do the right thing and recall these units and fix them at no cost?

-Richard

 

[JKmotorsports]

I took the truck to my GM dealer and here is what they did for the fix...
You need a GM scan tool to do this - they are about 3 grand. Unless someone can give me an idea of how to get my hands on a scan tool for a WHOLE lot less - this problem is not for the "do-it-yourselfer".
-Richard

This procedure only works with 03-up trucks with Class 2 databus systems. The systems on the newer trucks uses the BCM to decipher different voltages from the PDM and perform the related commands. The advantage of this is less wires, less current draw, and the overall ability to do more with less.
The older trucks used a straight forward reversing polarity relay/switch design. There was no computer needed for this operation, therefore, lacks the ability for the said system to be "reset" or reprogrammed.

 

[Roadmonster]

Actuators are more than likely getting weak. There is less strain when the motors are locking rather than unlocking because of the latching mechanism, which could explain why it locks but doesn't unlock. I have customers come in with the exact same problem all the time and I end up replacing the actuators with new ones.

Thanks for your response.

(We are still living with this problem.)

Just to clarify:

If all doors lock, and only the driver's door and rear barn doors unlock, then there could be three bad actuators for the other doors?

Is this normal, for three actuators to go bad at the same time?


Should I go to a shop and have them tested, or should I just buy three new actuators and hope that is the problem?

I looked at the cost of actuators, and I don't want to just throw parts at it. Can't afford that at the moment.

Thanks again for the help!

Stewart

 

[marinekilz]

well I would find a wiring diagram of the locking system. See if all three are in series to be unlocked. If you can't find one I will dl one tomarrow for you and post the link on the forum.

http://www.4shared.com/file/2654532...7L_VIN_R_-_Luxury__Door_Locks_And_Fuses_.html

Wasn't sure if yours is the luxury model, but here is both