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? Could it be in my BCM?