2007 Pontiac g5. Car starts fine, but won’t allow me to shift into drive for 2-5 minutes, and then it shifts perfectly fine. During that 2-5 minutes, the doors make a locking and unlocking sound at random intervals, anywhere from every .5 second to 10 seconds.
Sounds like the ECU is going bad.
There’s no way door locks are on the same circuit as AT solenoids. But it sounds like it could happen at the same time due to a compromised harness or wire. Unless you’re solid with electrical you need to give this to someone who is. I don’t believe it’s the ECU like another comment said. When a car cools it contracts and the gap between wires becomes greater creating an “open” or vice versa when it becomes hot the wires or other items expand and can “short”. If it was a short you’d likely have a blown fuse somewhere. You need a wiring diagram and to chase the door lock circuit. Likely something will present itself visually. Check wiring harnesses near spots that vibrate since they can run through.
I don’t know if that’s the case, but some cars don’t let you shift into drive or reverse (or unlock the parking brake) if there’s a door open. Even if they’re physically closed, there could be some problem and the module getting a door open signal.