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Malfunctioning electric locks drawing down battery

Good morning everyone,

1996 Saturn SL2. The electric locks have been malfunctioning such that they will suddenly lock and unlock continuously until the battery is dead. It occurs for reasons unknown - like the locks have a mind of their own. Been occurring intermittently - about once every couple of weeks. Mechanic’s been unable to replicate the problem. I’m fairly clueless about cars. It’s an older car, obviously, but is otherwise okay - would hate to get rid of it for this reason but . . .

Any help would be appreciated. Thanks for your time.

Best,

PM

This sounds like a door lock controller located in the drivers side door. Some Japanese models of this controller have a history of doing this very thing. Its about $200 to replace.

Keith’s suggestion is good but may not cover all situations.

The fault could be in the Remote Keyles Entry module as well, which is typically located in the dash and not easy to reach.

If you are lucky it could be just the switch. Try just barely wiggling the switch and if it causes the locks to operate that may be the problem. If the switch takes a normal rocking motion to make the locks operate then it is going to be a module. Junkyard modules are cheaper but may not be reliable for a long period, you never know.

Is one of the fuses labeled central locking?
If so, couldn’t you just remove the fuse and save the battery?
That obviously wouldn’t really fix the problem, but at least you wouldn’t have a dead battery.

Another possibility is looking at the wires that go from the frame to the driver door. A short there could be another suspect.

The most likely suspect is the driver side lock switch has some dirty contacts.

This is an OLD post and the OP has not returned to tell us of the outcome.

@Keith, thanks for pointing that out.
I for one will stop wasting my time.