1988 Chevrolet silverado
-395,000 miles

My passenger side window stopped working. I cant roll that window up or down, yet the driver side works perfectly fine. I was hoping I could fix it myself since I enjoy learning how cars function.

Did the motor go bad?
Did the switch go bad?
Did i blow a fuse? (im guessing no, since the other window works)
How to I test the motor and or switch?
How do I take off the door pannel to do the test?

 

the first thing you could try is checking the wiring it's very simple in these types of trucks I had the same problem in my 88 silverado suburban. stuff rattles loose over time and I've found that a lot of the wiring is getting crusty and brittle in my truck so that could always be an issue too.
step 1: Using a Multi- Meter, check the window switch for continuity. Does it open and close?

Step 2 : Checking the overall function of the Switch. flick the switch back and fourth.
Does the unit have good spring tension
? or is the back and fourth motion of it "sticky"

Step 3 : if the first 2 are good I've tried testing the motor by cutting the two wires ( my window was stuck down and it was overcast) and touching them together in order to actuate the motor. My window went up after that leading to the conclusion that i had a bad switch which I replaced and simply reconnected the two wires via splicing butts.
BAm!
my problem was solved