1996 Toyota Camry unlocks and locks itself

Question

my 96 Camry started locking and unlocking itself sometimes while driving and sometimes when not driving I will go to get into my unlocked car just to find it lock. It didn't really bother me til last week when it locked itself and my key would not work. I don't know how to break in to a car so I was stranded for 4 days.

Finally just now, I thought I would go try again, and it was unlocked lol.

So in the meantime I've wedged folded up cigarette packaging paper into the lock inside to hopefully prevent it from locking me out again.

How can I fix this, I am clueless...

Answer 1

You could try unplugging each lock switch one at a time(or all at once) and test to see if a switch is shorting.

If the car has an aftermarket security system you could try removing it from the door lock system.

The wire loom that run into the doors can also be suspect.

You should probably have a locksmith look at your key and lock cylinder so that you don't get locked out of your car again.

Answer 2

If you are going to fix this yourself it sounds a lot like either the wiring or switches for the door lock system is at fault. The door lock is just a solenoid (a relay like device except instead of changing electrical contacts it moves a plunger) so it's getting toggled somehow when you don't want it to. So, something is applying power to the solenoid on a random basis. First thing to look at is the switches. There are only two that control all of the locks in the car, and that's the two in the front door pull handles. They are easy to remove. Once removed try putting a DMM (Digital Multi Meter) in resistance mode across the switch and gently push on the switch without actually changing it's on'off state. If the resistance is stable at infinite or zero then the switch is likely good. If it's flaky, and jumping when you touch it (even without actually moving the switch handle) then you likely have a bad switch. You can also try the test listed earlier and just remove one of the switches at a time and see if you can reproduce the problem.

If it's not the switches, you can find the wiring diagram for the car online, or in some of the Chilton manuals. Given that the problem is power being applied randomly, it seems unlikely that something is shorting 12V to that solenoid with a short, but it's possible. Try looking for power at the solenoid (inside the door lock mechanism) when moving the harness. First place to check would be the wires that run between the body and the door, as they take the most abuse.

Honestly I think it's the switches, and it you test them thoroughly you'll find the problem. And more good news, they shouldn't be expensive to replace.