Window Switches?

[trenchwarfare]

The window switches only work when they want to in 90 suburban. The door locks also don't respond all the time. Should I replace the switches or the wiring? I've gone through this before in my towncar- tore apart the door thinking the motor was bad, took apart cables and tracks, only to find the switch was bad.

[tbplus10]

Use a multimeter to verify power at the switch, then verify power at the motor connection (make sure you have the ignition key on, I've made the mistake of leaving it off while doing power checks).
If you've got power into the switch but not out, bad switch.
Power into the motor but no reaction, bad motor.
I suspect in your case tho you have a bad fuse holder or shorted wire powering the system. This will be in your fuse block under the dash.

[30 Yr GM Tech Burn-out]

Window switches are notorious for intermittent ops. Replace-em Be sure to check for clean-tight pin contact to the switches.
Power door locks are a different story.
If ya got some kind of noise happening when you press the switch...The switch is good
Ive replaced Hundreds of worn out door lock actuators on that year body truck. 1 for each door.
You will need to remove panls and grind 1/4 rivets off to get them out of the door. Along with linkages.
Sounds like normal 18 year old truck stuff. You probably need to replace the front door hinge pins and bushings too.....The doors hard to close...Drop when opening.

[Gmcsuvguy]

Check for broken and/or cracked wires in door boot. #1 problem