I am looking for some help with a weird problem. I have a 90 k5 blazer with power windows locks windows and mirrors. Here is my problem the back window will go up and down from the dash switch but not from the key switch. Another problem I have is the power door locks don't work.
I have a wire grounding out in the power door locks that I am trying to trace and I am wondering how to pull the rear door lock assembly to check the wires. Are thes 2 items powered by the same source?
Does anyone have pictures of how to remove the rear lock assembly. and does any one know where the relay for the door locks is?
Thanks for any help.

 

These two systems are independent of each other since you have to have a key to use the rear window regardless of whether the other doors are locked or not.

The rear gate needs to be opened up to get the lock cylinder out. You need to remove the inner panel, run the window up until you see the retaining nuts for the outer escutcheon as it is called (the chrome piece that the key cylinder goes into). You may have to either disconnect and jumper the gate open switch or disconnect the drive cable from the motor and operate the window manually with a power drill so that you can move the regulator.

Once you get these two retaining nuts off, the outer escutcheon will basically fall off so watch out. Check for operation at that point by jumping between wires to operate the window motor. You can also check for continuity in the key cylinder when turned appropriately for up & down operation.

 

Atually the power door locks and the key switch for the rear window are on the same circuit. The dash mounted rear window switch is on the same circuit as the ign switch. The rear window key is on a power all the time circuit same as the power locks. I atually found the problem with the power door locks that was tripping the circuit breaker now everything works again. I was not able to get at the nuts I had the panel off and the window up but no luck finding the nuts let alone getting them off.

Thanks For the help I got it fixed anyway.

 

Well, in that respect, the main power, yes you are correct. I thought you meant that the doors being locked or the lock system malfunctioning (aside from the power side) would affect the rear window operation. I have seen where the power locks would flake out due to a switch problem and it did not affect anything in the back. I misunderstood the nature of your problem.

Glad you got it figured out.

 

I am glad there are people like you on web site's like this that are willing to help out people like me Thanks much Ross g