How do you repair electric door locks on a 1997 Chevy silverado 1500?
Kinda depends on what's wrong with them, which is why you
diagnose the problem first. If your key works for locking and
unlocking the doors, and they open and close fine, you can rule out
the door latch. If you just hear a buzzing sound when you press the
lock/unlock button, then it's your actuator which needs to be
replaced... if your latch is bad, it can burn out the actuator, as
well.
If you're getting nothing at all, then start by taking a test
light to your fuse panel to make sure the fuse is intact... the
diagram on the back of the fuse panel cover will tell you which
fuse it is. If you have power on both poles of the fuse, then you
need to take off the door panel... remove the bolts which hold the
armrest on and take off the armrest, and disconnect the switches
from the underside of the armrest (those switches will either be on
the armrest or on the door itself, depending on model year)...
wherever your switch for the PDL is, diagnosing it will be the
same... one pole on the plug to the PDL should be hot at all
times... use your test light to ensure you have power to that
switch. If you don't, then you need to trace the wiring from the
switch back to the fuse panel and find the fault in the wire. If
you do, then you take a trim puller around the interior door trim,
and pull that off. Disconnect the plug to the actuator, plug the
switch back in, and see if you have power to the actuator when you
depress the switch. If you do, then the actuator is bad. If not,
trace the wiring from the actuator to the switch and find the
fault.
While you have the door panel off, work the linkages to ensure
the door latch functions like it's supposed to, and ensure they're
all connected and undamaged.
Replaced the actuator, verify that it's working, and reassemble
the door.