2006 Hummer H3 Door sensor

Here is some info:Some customers may comment that the "Door Ajar" lamp comes on, chimes sound, or door locks cycle while driving.

Cause
The swing gate switch plunger may not be sufficiently depressed when the swing gate is closed due to door fit variation.

Correction
Open the swing gate and test the swing gate switch plunger by depressing it for approximately 20-30 seconds. The dome light should shut off.

Loosen the striker bolts (1).
Adjust the striker (2) forward, towards the front of the vehicle, 2 mm (0.08 in).
Re-tighten the striker bolts.
Tighten
Tighten the striker bolts to 25 N Â m (19 lb-ft).

Important: A good swing gate fit will position the plane of the door approximately 5 mm (0.2 in) forward of the rear edge of the taillamps. The swing gate should not be flush with the taillamps.

Close the swing gate. Verify that the top right corner of the swing gate does not contact the roof panel when closing the door. Verify that the swing gate latches securely and confirm that the dome light goes off after the normal interval.
Open the swing gate and close such that only the secondary latch is engaged. Confirm that the "Door Ajar" indicator in the IP cluster is illuminated.
Try this and post back with what you find or if you need more help.

Remove all 5 door jamb switches and let the lights go out. With all doors open, start plugging them in one at a time. Shut each door after plugging the switch in and installing it. Wait for the lights to go out with each one. When the lights stay on, that is the door with the bad switch. Another way is bench test each switch with an ohmmeter, pushing in the plunger should cause the circuit to go open. Also, check each switch connector for moisture(corrosion). Typically it is the drivers, or rear gate switch that fails, but others can too. The last one I did was at rh rear door.