Door Lock Issues Please Diagnose

ram360 said:

I have been having some issues w/ the door locks (94gt). Basically they both lock/unlock w/ the key just fine. Only the drivers side opens w/ the key fob. None of the doors lock w/ the key fob and the door lock switch inside the car will not lock or unlock the doors at all. I can hear a clicking come from the drivers side truck area when I push the buttons but nothing happens. Is there a relay back there? The trunk opens w/ the fob and key just fine though. I don't get it...I tested the fob at autozone and it functions normally. Obviously something in the car is fubar...ideas?

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Thats a tough one not being there.. I suppose the first thing I would do is pop the drivers side switch panel out and use an led tester (not a test light, because you are testing for ground and 12v) and see if you are getting power to both sides of the switch) IIRC, the doorlocks are multiplexed from the drivers switch, so if there is a problem there, neither side will work.. but I could be wrong, I work on too many different cars and not that many mustangs..

Either way, the doorlocks are reversal rest at ground meaning when you hit lock, the pink/yellow goes to 12v while the pink/purple goes to ground, and when you hit unlock, the pink/yellow goes to ground while the pink/purple goes to 12v... This is relayed through the body control module which is under the drivers side dash somewhere..

The keyless module is in the driver's side of the trunk. That's the clicking you hear.

I agree that checking I/O power and ground at the master switch is the place to start. Once that's known to be copacetic and works, if the keyless module isnt working properly, deal with that afterwards.

have you tried cleaning the contacts INSIDE the door lock switches?

when you press the door lock switch,nothing happens,right?

might not solve all your problems,but may get both your driver and passanger side door lock switches working.

i had same problem.both door lock switches did not work.i cleaned the contacts now they work fine,but i do not have keyless entry on my car.

i attached a small video on how to clean the switch.sorry,not a very good quality,my other cam is in my girl's car

hope this helps alittle


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