I just purchased a 2011 Silverado 1500 and I noticed that I cannot lock or unlock the doors using the button on the door. This is the same on the driver and passenger's side. However, I can lock and unlock the doors with the key fob. Also, when I start the car and put it in drive, the doors lock, and when I shut off the car the doors unlock. Hmmmmmmmm

 

You have a glitch in the system for sure. It's a warranty issue so let the Chevrolet technicians handle this. You paid for the warranty when you bought your Chevrolet.

 

Oilcanhenry, It's a 2011 and I bought it from a private party, so I'm stuck with the mystery.

 

Do you have bucket seats and power mirrors? The way the switches and related circuits are wired is different depending on that. I can post the wiring diagram if you tell me which setup you have.

Otherwise, all the fuses for the door locks are in the instrument panel fuse block at the left end of the dash. They are labeled as lock or unlock 1&2 depending on the setup. You’ll also want to check the fuses labeled PDM & DDM as these supply power for the door switches.

 

I believe this is normal. We have a '14 Equinox and the doors lock when put in drive and unlock when put in Park.

 

Gumby, I do have bucket seats in the front and automatic mirrors. I have gone through all the fuses and they all ohm out. Please provide me the wiring diagram, so I can pint point the difference between the key fob locks and the door locks.

 

Doug, I was trying to convey that the locks work, when I put the truck in drive or park, and when I press the door lock/unlock on the key fob. What does not work is when I press the button on the door to lock/unlock the vehicle. Both driver and passenger doors do this.

 

I’d recommend verifying power on both sides of the fuses with a test light as opposed to just ohm checking them. I’ve only seen it once, but I’ve encountered fuses that seemed to have no resistance and “looked good” but would only have power to one side when using a test light. I’m not sure if they were just dirt cheap fuses or what, but since then I’ve always used a test light (and for me, it’s faster than pulling them and using a meter).

Have you installed any accessories that required splicing into the dash harness? What about some kind of monitor that plugs into the OBD port? What about a phone charger or GPS? For about the past 20 years, GM has had an on-going service bulletin about aftermarket accessories interfering with normal vehicle functions and the effects can vary greatly. The easiest test for this is to just unplug the accessory and see if normal operation returns.

The wiring diagram is below. It would appear this is a BCM problem as the door switches are just inputs and the BCM controls the locking/unlocking of the doors. That said, one weak point in all vehicles is the section of the harness that passes through the boot between the door and cab. It’s unlikely that both door harnesses would fail at the same time, but if the driver door failed first and the passenger second, maybe the PO didn’t know because they never used the door buttons; or maybe they ignored the problem. If you find the harness to be at fault, I recommend just getting the replacement harness from GM because usually one or two wires going open means the rest aren’t far behind.