AK49BWL
GMT400 Forever!
I had a problem with my 03 Blazer's driver window getting stuck all the way down due to age and very likely over-use of the window auto-down feature. The auto-down feature works by monitoring the amperage draw of the window motor to detect when it has bottomed out ... Problem is there's a delay between bottoming out and the auto-down shutting off, which can cause the motor windings to overheat over time, or damage the motor armature. So I disabled auto-down permanently after tearing my motor apart to unstick the window. I'm still using the same motor, I just don't go all the way down with it anymore, and when I put it up, I tap it back down so there's not excess stopped pressure on the motor (because it's gotten stuck UP, too lol). This post applies to GMT400 trucks 95+ and S-Series trucks 98+, the switch bodies are fully interchangeable. Shown here is the two-door switch, four-door is the same plus a few more terminals for the rear window switches.
This post assumes you already know how to remove the window/mirror switch panel from the door and disconnect the wiring harness connectors. You'll start with this:
The blue circle is the part that holds the window switch body to the bezel on each end of the switch body. Flat blade screwdriver pry it out of the bezel. Carefully, the plastic may be brittle (mine weren't). Red circle shows the part holding the switch body's cover on, pry it off (keep the cover straight on both ends when pulling it off, the electrical connector terminals are part of the switch body, not the cover). You'll end up with this:
The circuit board with the relay on it is what controls the auto-down functionality. Red circles: You will need to use needle nose pliers or something similar to straighten these little tabs so they line up with the slots in the circuit board. Do not break them off. It takes very little pressure to twist them. Once you have them all lined up, start prying the board up from the edges until it comes out of the switch body. It might be a bit of a pain coming out, just be patient lol. Once out, flip the circuit board over:
Circled in green is the trace on the board you should use a sharp object to cut, where the red line is. Make sure you fully cut through the trace, but not all the way through the board itself lol.
Reinstall the board to the switch body, twist the little tabs back to hold the board to the switch body again (don't need to go too far with them or you risk breaking them off), put the cover back on, reinstall in the truck, and enjoy having full control over your driver window at all times!
This can be reversed by simply soldering a jumper over the cut in the trace you made. Me personally, I have several spares if I ever have a desire to use auto-down again. You can probably just rip off the little 8-pin IC to avoid having to pull the circuit board off, but that's a little harder to reverse lol.
This post assumes you already know how to remove the window/mirror switch panel from the door and disconnect the wiring harness connectors. You'll start with this:
You must be registered for see images attach
The blue circle is the part that holds the window switch body to the bezel on each end of the switch body. Flat blade screwdriver pry it out of the bezel. Carefully, the plastic may be brittle (mine weren't). Red circle shows the part holding the switch body's cover on, pry it off (keep the cover straight on both ends when pulling it off, the electrical connector terminals are part of the switch body, not the cover). You'll end up with this:
You must be registered for see images attach
The circuit board with the relay on it is what controls the auto-down functionality. Red circles: You will need to use needle nose pliers or something similar to straighten these little tabs so they line up with the slots in the circuit board. Do not break them off. It takes very little pressure to twist them. Once you have them all lined up, start prying the board up from the edges until it comes out of the switch body. It might be a bit of a pain coming out, just be patient lol. Once out, flip the circuit board over:
You must be registered for see images attach
Circled in green is the trace on the board you should use a sharp object to cut, where the red line is. Make sure you fully cut through the trace, but not all the way through the board itself lol.
Reinstall the board to the switch body, twist the little tabs back to hold the board to the switch body again (don't need to go too far with them or you risk breaking them off), put the cover back on, reinstall in the truck, and enjoy having full control over your driver window at all times!
This can be reversed by simply soldering a jumper over the cut in the trace you made. Me personally, I have several spares if I ever have a desire to use auto-down again. You can probably just rip off the little 8-pin IC to avoid having to pull the circuit board off, but that's a little harder to reverse lol.
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