I recently had a total loss of power window operation. No switch would work any window. I checked the fuses and they were good so I ordered and replaced the relay. Problem not fixed. I checked voltage at fuse and got 12v and checked brown wire and red wire at relay and get no voltage. Any idea what my next step should be?
Gary
'85 245GL

 

Check the switches on your door. Will any of the other switches work on the other doors? That is my only idea.

 

None of the switches are operational. The brown wire at the relay DOES have 12v.

GaryMc

 

There should be a minimum of 4 wires on the relay. One will always be hot w/ key on, coming from fuse block. Opposite it should be hot with switch depressed going to window motor. One wire should go to chassis ground and opposite should be a signal wire coming from the switch that will be hot when switch is active. It should be noted that the majority of issues are at the master window switch. This is because it is used the most, is horizontal and catches a lot of crap. If the master switch is fubar'd, no other switch will work. That's because power goes first to the driver door master. So...that's where to start. It's not absolutely necessary to pull the door panel; the master can be pulled without it by prying up with a pocket screwdriver on the long ends as that's where the clips are. Be careful to avoid dislodging the individual plugs and mixing them up.

 

ah lookie here.... http://www.k-jet.org/files/greenbook...985_PRELIM.pdf

'electric windows - 4-door models' is about 80% of the way through that.

ok, looks like fuse 10 (brown at the relay) supplies the power to the window motors, while fuse 12 which is switched by the ignition and is blue-yellow at the relay, triggers the relay coil. the red wire at the relay comes off pin 87 and goes to each of the window switches (but changes color at the door connectors...

so, with the relay removed, and the ignition switched on, you should measure power between relay pins 85 (ground) and 86 (fuse 12 switched power), as well as 85 (ground) and 30 (fuse 10 unswitched power)


anyways, jumping relay pins 30 and 87 together should bypass the relay entirely.

 

Narrowing this issue to the master switch, should I not be able to activate the window by jumping from red to black on the driver window and bypass the switch?

 

well, if both front door switches aren't working at all, I'd guess the problem is upstream, which is the relay and/or fuse panel and/or wiring. the passenger door window works even if the driver door connector 'F' is completely disconnected.

the back door windows get their power via the drivers side switch module.

at the drivers side switch module, with the car switched on, can you read +12V relative to chassis ground at the various red wires that are all daisychained ?

 

No voltage at any of the red wires, I went back and jumped 30 and 87 on the relay and the windows work. I guess this new relay isn't any good. Any recommendations for a supplier of reliable replacement units.

 

maybe its the wrong relay. examine the pin numbering closely, and compare it with the schematic... on the page after the wiring diagram, is the layout of everything, including relay "A"... brown goes to pin 30, blue-yellow to pin 86, 2 reds to pin 87, and two blacks to pin 85.

if the relay shows its schematic on the side (many better ones do), the coil is between pins 85 and 86, and the N.O. (normally open) switch contacts are between pin 30 and 87.

 

The pin #s match the wire locations. This brand is Wehrle. I see another brand, Standard Motor Products, listed by the same supplier, Partsgeek.com. This one is about three times the cost and says "Genuine Intermotor Quality".

 

then I'd verify that there's 12V between pins 85 and 86 when the ignition is turned on (relay unplugged). if there is, then yeah, bad relay or something. if there isn't, well, pin 86 goes to a blue-yellow wire to fuse 12, and the other side of fuse 12 has a blue-yellow wire to pin 15 of the ignition switch, which provides power in II (run) and III (start) positions, but not I (accessory).

 

Thanks for all your help. I installed the new, proper, relay and all windows are once again working.
GaryMc