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Author Topic: Rewiring power windows to fix loss of power  (Read 2265 times)

Offline Teranfirbt

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Rewiring power windows to fix loss of power
« on: Mar 09, 2014, 11:50:15 pm »
I had some issues with my passenger window not rolling up. Rather than just trying to clean the switch contacts again, I put together a more permanent fix using some relays.
I've attached the wiring schematic for the fix, it's pretty simple. It does require that the relays have an 87 and an 87a pin, 4 pin relays and ones that have 2 87 pins won't work.

Required materials:
2x STDP relays (pins 30, 85, 86, 87, 87a)
20ish feet of 14 gauge wire for power, ideally red, black, and orange
10ish feet of 18 or 20 gauge wire for signals, ideally 3 different colors
12 female and 2 male quick disconnect blade terminals
A way to splice power and ground wires (solder, crimps, whatever).
Heat shrink to protect solder joints
3/8" split wire loom
electrical tape

The basic idea is that you're replicating the function of the switch using relays. When nothing is switched, both wires on the motor are at ground through the 87a pin. When you press the window switch, it clicks over one of the relays, which puts 12V to one side of the motor, but remains grounded through the other. When you press the switch the other way, it power the other side of the motor and makes it go the other way.

When you first hook everything up it might go the wrong way (up is down and down is up). The simple fix for this is to switch the wires connecting the switch pins to the relay 86 pins.

Here is the whole thing installed in my window: https://1drv.ms/u/s!Ar_YC0VL0CgTliGxvLy105EamSDP?e=WGMLJw

The green connector for the lock that is originally clipped to the white plastic piece is now zip tied out of the way below the opening.
« Last Edit: Apr 25, 2020, 02:41:27 am by Teranfirbt »
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