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Door Lock Problems

9.8K views 13 replies 4 participants last post by  Mrjonesez  
#1 ·
SO........ I have been beating my brains against the walls on this one. My drivers side door lock stopped working. I changed out the actuator and nothing......... I checked the fuses and all is well. I ohmed out the wire from the fuse box to the switch connector (good). I ohmed out from the switch connector to the actuator (good). All the other locks work. I bought another new actuator (still nothing). I just bought a used switch of the same part number from ebay and it comes in Saturday. The switch on the drivers door still works all the locks BUT the driver door one. I'm leaning towards the computer or the actual plug that goes into the actuator or the switch BUT they still ohm good........

Do you guys think the switch has anything to do with it?

I plugged in the passenger door switch to the driver door. Could that have messed up the computer? Am I going to be super happy when the switch comes in? Am I going to have to have the used switch programmed at a dealer?
 
#12 ·
I don't think you messed up the computer. The switch is likely bad. These series trucks have problems with the door switches and looking at them makes me tend to believe they are cheaply made electronics. The passenger door switch is not exactly the same as it does not have a key cylinder function. The drivers door does have key cylinder wiring that goes thru that switch module. If you check, you should see that the passenger door wiring has 1 less wire to the switch.

Ray, strangely enought, according to a 2008 electrical diagram I saw awhile ago some of these trucks do not have door modules. They do have a lock/unlock relay controlled by the BCM and its in the LBEC.
(left bussed electrical center).
Additional info, there is a 15A mini fuse for each door called an unlock drv. Check for a blown fuse too.
Thank you for this! You are correct the passenger is different. Which I guess is why it didn't work. The new used switch comes in today instead of tomorrow now I see. I'm excited!!!!!
 
#4 ·
That truck has a door control module inside the door.
The module will operate the locks, the window, the mirror.
It has 12v power and a computer bus.
The lock commands are sent to the Door Control Module over the bus.

Do you have a remote key fob?
 
#11 · (Edited)
I don't think you messed up the computer. The switch is likely bad. These series trucks have problems with the door switches and looking at them makes me tend to believe they are cheaply made electronics. The passenger door switch is not exactly the same as it does not have a key cylinder function. The drivers door does have key cylinder wiring that goes thru that switch module. If you check, you should see that the passenger door wiring has 1 less wire to the switch.

Ray, strangely enought, according to a 2008 electrical diagram I saw awhile ago some of these trucks do not have door modules. They do have a lock/unlock relay controlled by the BCM and its in the LBEC.
(left bussed electrical center).
Additional info, there is a 15A mini fuse for each door called an unlock drv. Check for a blown fuse too.
 
#14 ·
SO........ I have been beating my brains against the walls on this one. My drivers side door lock stopped working. I changed out the actuator and nothing......... I checked the fuses and all is well. I ohmed out the wire from the fuse box to the switch connector (good). I ohmed out from the switch connector to the actuator (good). All the other locks work. I bought another new actuator (still nothing). I just bought a used switch of the same part number from ebay and it comes in Saturday. The switch on the drivers door still works all the locks BUT the driver door one. I'm leaning towards the computer or the actual plug that goes into the actuator or the switch BUT they still ohm good........

Do you guys think the switch has anything to do with it?

I plugged in the passenger door switch to the driver door. Could that have messed up the computer? Am I going to be super happy when the switch comes in? Am I going to have to have the used switch programmed at a dealer?
I know this is old but I fixed mine and did some other stuff as well. Mine 2009 sierra. Driver actuator wasn't working. Passenger worked fine but just from Passenger controller. First thing i did was replace door switch. I was now able to operate from that side the passenger locks.
The next step is the hardest. Take apart driver door to get to the actuator connector. Used a test light. My multimeter was not fast enough to keep up with momentary switching. What you want to test are the larger wires on the connector.
Mine was a orange and a gray. Test each with lock and unlock switch. If one is dead then go to the fuse box.
Your door wires plug into a connector there.
Test at that spot with your test light. Lock and unlock as before. If you have juice then you have a break in the wire right in the boot where the door hinges. My problem was there. If you have power at the actuator and it is not working then replace it.
Also while in there take your window switches apart and give em a thorough clean if those are acting up. I used cue tip on the contacts to remove the crud. After all that everything is working like brand new.
If you decide to tackle the switches do it sitting down on a clean table. Its not something your going to do with success on the floor board of the truck . Hope this helps