Sedan LF Window problemo...

[slammin.e28]

My 1991 sedan's left rear window will not go down. (Realized I hit LF in the title, sorry.)

I swapped both the front and rear switches out for known good ones (from the same car) and nothing. I got a spare window motor & regulator, expecting the worst. I decided to test the new motor outside of the car. Hook it up, hit the up button, it goes up, hit the down button, nothing. (This is using the front switches by the shifter.) I then tried the rear switch on the door. Nothing. No up, no down.

I swapped the switches again to see if that made a difference, nope. I'm thinking I have some ugly wiring problem now. All the switches light up, no problem. It's just the rear doesn't work at all, and the front switch, for the LR window only goes up.

Gimme some suggestions, where should I look first? What should I test? I'm eyeballing the ETM right now, but my netbook screen is oh so small....

[InuFaye]

Selling your E30.

[1mz]

In the same boat.. LR window motor doesn't seem to be functional. However I have yet to try applying 12v power directly to the motor itself - how about you? tried that yet?

[1mz]

-- and where in the 540 are you? I'll be in harrisonburg tomorrow hah

[slammin.e28]

Here's what I figured out:

In the door, the connector from the door switch to the window motor is a BL and a BK. The BU is + DOWN, - UP. Thus, the BK is + UP, - DOWN.

Notice, the switch on the door HAS NO BR wires (ground). This indicates that the system MUST be grounded elsewhere, but where? It is grounded THROUGH the switch on the center console. Thus, for it to work correctly, the wires in the console must be in tact. The wires going TO the console must me in tact. The switch must be in tact. The BR at #5 on the console switch = UP. The BR at #4 = DOWN.

The other wires are as follows:

GN/GY = Power (+12v)
BK/YL = +DOWN/-UP
BU/GN = +UP/-DOWN
GN/BU = Rear window lockout switch.

Switch terminals:
@ Console
1- BU/GN
3- GN/GY
4- BR
5- BR
8- BK/YL

@ Door
1- BK
3- GN/BU
4- BU/GN
5- BK/YL
8- BU



Electrical diagrams.

I decided I would try grounding out the BU/YL wire at the door. Viola! Up and down at the door. For now, I have a wire running from the BL/YL on the door switch to a ground. Once I get the console switch fixed, I imagine the whole system will work fine. I now have down at the console, but no up.

Testing voltage at the window connection, I get full voltage (car running ~13v) when my dad hits the DOWN. I get .3v when he hits and holds the UP. Problem? Yup. I'm still working on that one.

-- and where in the 540 are you? I'll be in harrisonburg tomorrow hah

I'm located in Waynesboro, well, OUTSIDE of Waynesboro...lol.