My rear window don't work on either side. The prevous owner had this car restored and the rear seat switches were not installed. Do they need to be installed to complete the curcuit? Since both aren't working I doubt it's the motors and probably elidtrical. Any help would be greatly appreciated. Byron [email protected]
E9 Rear window regulator
- Thread starter blamotte
- Start date
Rear windows don’t require rear switches unless someone has boogered things back there. Put a volt meter on the wires and start testing for current etc. and make sure your front switches have correct wiring.
In first place tell us more about the installation:
- which motors are installed? Flat sardine tin?
- is the original harness running from the center console back to the rear windows installed or do the installation look homemade?
- can you move the windows manually by turning the plastic white gear wheel on the motor?
- is there a terminal block with two cores installed next to the motor? If you know what you are doing you may take battery plus and tip on either of the terminal screws, the drive should start moving. Be careful, avoid short circuit!
- which motors are installed? Flat sardine tin?
- is the original harness running from the center console back to the rear windows installed or do the installation look homemade?
- can you move the windows manually by turning the plastic white gear wheel on the motor?
- is there a terminal block with two cores installed next to the motor? If you know what you are doing you may take battery plus and tip on either of the terminal screws, the drive should start moving. Be careful, avoid short circuit!
jmackro
Well-Known Member
Rear windows with the original motors can be tough to keep working. Basically, the motors lose torque, the grease on the window tracks hardens, and if the regulators aren't perfectly aligned, the motors just don't have enough oomph to raise the windows. Lots has been written on e9coupe.com about e9 power windows if you'd like more detail. Most likely this is your issue (though sure, the restoration shop may have simply not connected the wiring properly).
TomHom's questions are good. He mentions removing the circular plug over the white gear wheel and manually turning the mechanism to raise/lower the windows. Before doing that, remove the plug and watch the white gear wheel while someone actuates the appropriate window switch - can you see the wheel trying to turn? If it is turning a bit, the wiring is OK but the motor isn't able to overcome the load.
TomHom's questions are good. He mentions removing the circular plug over the white gear wheel and manually turning the mechanism to raise/lower the windows. Before doing that, remove the plug and watch the white gear wheel while someone actuates the appropriate window switch - can you see the wheel trying to turn? If it is turning a bit, the wiring is OK but the motor isn't able to overcome the load.
Last edited:
I was under the impression that the switches had to be installed in both console and rear to get the windows to work. Hmm, it was 6 years ago when I tackled this, so maybe cranial cobwebs. Also recall the drivers rear window works with no key in the ignition when the driver's door is open. Tell me at least I got that part right!
I believe that’s in later cars, my ‘72 does not have this feature. Interesting about having all switches in place, I could have sworn I’ve activated the back from the front with the back switches out as they are wired in duplicate
Up to '72 the flat type motor was installed, with two windings, one for up, one for down. The switches centre console/rear were connected in parallel. It was possible to operate the window with only one switch installed.
From '73 onwards the black type of motor was installed. This has only one winding, changing the polarity will change the direction. This installation requires both switches to be installed.
Thomas
From '73 onwards the black type of motor was installed. This has only one winding, changing the polarity will change the direction. This installation requires both switches to be installed.
Thomas