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Car unlocking itself randomly

Just a few days ago I encountered my 2008 Pontiac G5 unlocking itself randomly. I checked the fuse box and fuses are fine, I did test with a new fuse same result. Exactly what’s happening is, the power locks randomly unlock (never lock), and hitting the power lock on driver’s side only works to unlock, not lock; hitting power lock on passenger’s side works for both. The random unlocking is simultaneous on all four, no single door is having an issue.

Am I relegated to going to the dealer? A friend with some car knowledge said I need a wire schematic to determine where the short might be if that’s the case, or it’s impossible. Thanks for any help folks!

Have you ever left the windows down and gotten rained on? There is a chance that the drivers door switch has been contaminated/wet/whatever, and randomly is making connection to unlock. Would also explain the ‘not locking’ by that switch. You can try buying a can of contact cleaner (some say WD-40 is OK to use in these situations), and, after pulling the appropriate fuse, using the included spray straw, lightly shoot a little in there, work switch back and forth, repeat. I have usually removed the door panel and done it from the underside for better results, but it’s worth a try from the topside. May not be your problem, but I have run across this on a few vehicles.

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I think @OldcarsRbest is on the right track. Do you need the dealer to fix it? No. Indie mechanics can fix things like this as can competent DIY’ers. Are you or your friend a competent DIY’er?

Switches tend to get a lot of wear and it doesn’t take much to damage one, water or otherwise. Your friend is also right, you need a schematic (and the ability to read and understand it) and the tools to trace down the problem. But just replacing the lock switch rather than trying to clean it may be a good and cheap “throw some parts at it and hope it fixes the problem” type of solution.

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Ok, so I pulled the door fuse from front passenger side fuse box, as I do not have a fob or remote key or anything, I’ve always manually locked/unlocked. Is this the fuse you guys are talking about, or you mean in the door itself?

Edit: I had 2 fuses, both “15”, both working fine that I tried so it’s not the fuses

If the switch on the pass. door is not working now, then yes, that’s the correct fuse. I meant to pull it while doing anything (cleaning/replacing) to the switch. Then, once you’re done, replace it and see if the drivers door switch works better.

BTW, your problem is NOT being caused by a bad fuse. You have power to the switches and locks.

No when I had the fuse in, all 4 door locks were unlocking, but on the driver side the switch was only unlocking, whereas passenger side switch was unlocking and locking. I have grabbed some wire schematics from TDB Wilson site and will take care next week to friend’s, hopefully figure out where the issue is. For now no fuse so it’s just manually un/locking, can’t have car randomly unlocked as one goes through the day! Yeesh these silly things that come up. Thanks for the help

Does it unlock by itself only when the car is parked in a certain location? Or does it do this irrespective of where the car is parked?

Hmm, IIRC yes they would unlock while driving. When unlocked, you could hear the unlocking at random times going off but of course once they unlocked they didn’t lock and unlock, as it’s only been unlocking.

Sounds more like a bad open sensor or switch to me, like the one that unlocks the doors when you put it in park, or a door open sensor on the drivers door.