I have a 1990 full size Blazer and the tailgate window will not roll up. I replaced the switch several months ago and it worked for a while. The problem has surfaced again. I have had the switch checked and it checked out as good. Does anyone have a diagram of the wiring so i can trace the wires from the switch in the dash to the motor in the tailgate?

Thanks

 

for starters kwerts, you're in the wrong section. you K5 boys have a section right below the 2nd gen section. but since i have a '90 'Burb with a tail gate, i'll give ya a heads up-get a new motor. i would have a periodic issue with the window going up. replaced the switch was fine for 3 weeks, then absolutely nothing! the motor worked, but was so damn weak, it couldn't lift the weight of the window. bought a new one from GM (not to bad, was just under $100 CAN, taxes in), comes with 1 yr warrenty, and is alot faster now.

 

*Moved to Fullsize Tech*

I agree, the motor is the likely cause. The reason why the new switch works for a bit is because it is new and will not have as high of a voltage/current hit when activated. The motor is the most likely cause of the whole thing. All that you really have to do is test for proper voltage at the motor. When you press up, the tan with white stripe wire should be hot. When you press down, the light blue wire should be hot.

 

Thanks guys - i did replace the motor with a used motor last year. But i will check the motor again since the one i put in was used. Appreciate your feedback.

 

I just posted this on another question. There is a safety switch on the drivers side latch inside the tail gate. it will not allow it to go up when the tailgate is down. I had this problem and was about to replace my motor when i found 2 blue wires that acts like a ground for the motors up switch. If you take the taligate fover off you should be able to see the wires over on the latch mechanism. Try that and let me know.

 

kwerts problem sounded more like the motor was shot (judging from what he wrote).
are you trying to say your safety switch wires were corroded, and caused your window to freeze?

 

ive always just bypassed the safety switch, just make sure that window is all the way down before you open it. to test the motor just run a hot wire all the way from your battery and touch it to either wire to see if it goes up and down. also... you can try running a ground all the way from the battery, ive had it happen before where the motor wasnt grounding.

 

im looking to by a cable drive for tailgate window 1989 chevy blazer full size i look on line, i cant find one. i appreciat thanks

 

LMC Truck sells them... ~#30 for the drive cable.