I have a very strange issue. My 2006 hummer H3 will only unlock the drivers door with both the key fob and the switch. When I press the lock buttons on both, they all will lock. When the key is removed from the ignition, again only the drivers door unlocks. I have replaced the master switch in the door, checked the fuses and relays, traced all wiring for breaks or corrosion and replaced the battery and terminals. I am at a loss and it's driving me nuts!!! Three garages cannot find the issue either. and have verified that the new switch I put in is not defective. And it seems to be intermittent. Every once in a while, when I pull the key it will unlock all doors but when i try it again right away, there is just a click again. And this seems to be after it is really cold outside and then the vehicle warms up. But as I said only once and every couple months or so. All windows work fine. Push the unlock once and drivers only unlocks, push it twice and there's just a click in the switch. Any help would be greatly appreciated. And I have tried all of the theories online: resetting BCM, switching relays, etc... Does anyone have a solution to this problem?

 

check instruction book, i think it can be programmed that way.
there are options...

 

Ran through all the program modes in the manual and its still doing it. It happened after a drain in the battery last year and at the time I had the window and lock issue. By replacing the switch, the window issue went away but the lock one remained.

 

Tried all 3 options in the book, even reprogramming the key fob. Nothing worked.

 

could be the door logic board/relays on that board.
i think that logic decides to unlock all on the 2nd click.
the unlock signal comes from bcm.
look at wiring diagram,its tricky!
those relays are soldered on the logic board.
you didnt change the board huh??

 

Yes, I changed the whole master switch which came with a new board. And the garages that I did take it to, tested it and said its working fine. They even tried a brand new one just to make sure. Do you think it could be the bcm?

 

you said when you click twice you hear a click so the bcm must be sending the signal?
i think the door logic decodes the 2 clicks to unlock all as opposed to one click opening the driver door.
sorry i cant help.
also the inside direct unlock button works for all huh? means relays/motors are ok.
that goes thru the door logic module too.

 

No, the inside direct unlock only does the drivers door. And your attempting to help, that is more than I can be thankful for.

 

ok then if the door module is new/ok?...then it looks like wiring/connector trouble.
you need to be looking at the door wire diagram.
i hear you can download svc info free. idk how. someone will.

 

Try unplugging and reattaching the passenger side window/lock control module. It might help.