Please help. My 2003 H2 is controlled by aliens. Opening any unlocked door causes all the power door locks to engage and lock. Leave your keys inside or in the ignition at your peril (ask me how I know). The key remote works fine and reopens all doors. But the next time I park the car and shut it off, the same thing happens. No trouble codes set. I replaced the power door lock/window switch, but no change. Any ideas out there?

 

Wow .That's a New one... I wonder if it's a Case of The OnStar Gremlin? All that stuff runs thru OnStar Module. One of the guys here might have an answer or suggestion.

 

Changing the DDM was a good call.

Seems like something is globally commanding the doors to lock based on any door ajar switch being activated, this a really odd due to the number independent systems involved, the common link being the BCM as follows:-

• Drivers Door ajar switch and lock actuator are wired directly to the DDM, controlled by the BCM
• Passenger Door ajar switch and lock actuator are wired directly to the PDM, controlled by the BCM
• Rear door ajar switches are wired directly to the BCM
• Rear door lock actuators wire to relays controlled by the BCM

Is there an aftermarket alarm system fitted or any other aftermarket kit installed?

Agreed Onstar is no longer supported so should either be removed or its fuse removed.

 

I would start with a scanner and watch all the door function's while opening the door and closing it,
That should revel what's going on, if not then re-flash the BCM
Pull the battery form the remote or try opening the doors with the remote out of range,
GM has some global functions like all doors lock when the truck is placed in gear, I believe you can turn these off

Have any of the modules been flashed recently

Just some ideas to look at,

Neal

 

i would start by reading the owners manule. and make sure it is not on default global close.
then i would check if there is an aftermarket alarm installed. which sounds more probable.

 

Good answers.... But I don't trust that Pesky OnStar Black WTF can I screw up next Box....L.O.L

 

Learn this one the hard way. When I replaced my master switches in the driver's door and everything went haywire. Call the Buddy at the dealer and he said those have a circuit board inside that need to be programmed, bring it in. $176 later it worked fine.

 

Are you behind in payments? Auto finance companies install a gps tracking device to control your ride.

 

And Insurance companies get the crash info from your Secret Squirrel box.

 

Thanks for the suggestions.
I disabled OnStar a long time ago.
I do not have an aftermarket alarm.
I recently replaced the driver's door power lock and window switch, which had stopped functioning. However, this self-locking behaviour occurred before that replacement and continues with the new switch.
I don't understand the suggestion of reprogramming the power window/door switch or how I could do that.
I will try the suggestion of opening the door with the key fob out of range. I never tried that since I always carry the key fob because of getting locked out.
I don't know if it's relevant, but earlier, I had a regular fault showing "Drivers Door Ajar" on the panel, even with the door properly closed. I replaced the door striker electrical switch, which has stopped that from occurring.
I should put zippers on the inside panel of my driver's door—it's been on and off more times than I can count.