1987 928 S4 power windows not working
05-15-2016, 01:25 AM
#1
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1987 928 S4 power windows not working
Need help with power windows please
1987 928 S4
My power windows stopped working, both windows worked before and they stopped working at the same time, so I don't think it is the motors, relay checks OK, fuse is OK, I have power to the fuse and to the relay, but no power to the switch. I did remove the relay and bridged the 30 to 87 terminal on the relay board but still no power at the switch.
I don't know if this may be related, my instrument gages have been jumping and flashers blinking and also the mirrors stopped working and the interior lights not coming on.
Appreciate it if anyone has any ideas.
1987 928 S4
My power windows stopped working, both windows worked before and they stopped working at the same time, so I don't think it is the motors, relay checks OK, fuse is OK, I have power to the fuse and to the relay, but no power to the switch. I did remove the relay and bridged the 30 to 87 terminal on the relay board but still no power at the switch.
I don't know if this may be related, my instrument gages have been jumping and flashers blinking and also the mirrors stopped working and the interior lights not coming on.
Appreciate it if anyone has any ideas.
05-15-2016, 03:48 AM
#2
Rennlist Member
It [obviously] sounds as though you have electrical discontinuity at a common node in the circuit and this would send me in the direction of the main fuse [No 15- agreed?] and you say this was good?
Presumably you have a set of wiring diagrams for your model year given your description. You have identified the terminals numbers correctly for bridging the relay [according to the wiring diagram] but you have power at the fuse so that eliminates the relay anyway.
The above suggests a problem somewhere between the fuse outlet and the point at which the circuit splits on the outlet of the central electrics G23. suggest you check for power at this location.
Given you appear to have other [seemingly] unrelated issues trust the mice have not been having a birthday party in the CE panel!
Good luck
Fred
Presumably you have a set of wiring diagrams for your model year given your description. You have identified the terminals numbers correctly for bridging the relay [according to the wiring diagram] but you have power at the fuse so that eliminates the relay anyway.
The above suggests a problem somewhere between the fuse outlet and the point at which the circuit splits on the outlet of the central electrics G23. suggest you check for power at this location.
Given you appear to have other [seemingly] unrelated issues trust the mice have not been having a birthday party in the CE panel!
Good luck
Fred
05-15-2016, 01:12 PM
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update 2
The fuse number 24 (interior lights) which I had replaced yesterday (the interior lights were working yesterday after replacing the fuse) is blown and interior lights don't work anymore. Also the mirrors don't work today.
checked the resistance between terminal 87 (window relay) and the socket at window switch and it shows open circut, I thought that should show continuity!
The fuse number 24 (interior lights) which I had replaced yesterday (the interior lights were working yesterday after replacing the fuse) is blown and interior lights don't work anymore. Also the mirrors don't work today.
checked the resistance between terminal 87 (window relay) and the socket at window switch and it shows open circut, I thought that should show continuity!
05-15-2016, 02:16 PM
#6
sounds like you have a short! start tracing the light wiring. on the original issue, i find that the contacts on the window switches get gummed up with carbon over time and need to be cleaned.
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06-06-2016, 03:41 PM
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I am not sure what happened, but after cleaning all fuses (the gray color corrosion or deposits) and replacing all the cheap relays (141.951.253.B , 5 places) all my gages are working fine and the windows are working again.
11-27-2016, 11:46 AM
#9
Intermediate
Need help with power windows please
1987 928 S4
My power windows stopped working, both windows worked before and they stopped working at the same time, so I don't think it is the motors, relay checks OK, fuse is OK, I have power to the fuse and to the relay, but no power to the switch. I did remove the relay and bridged the 30 to 87 terminal on the relay board but still no power at the switch.
I don't know if this may be related, my instrument gages have been jumping and flashers blinking and also the mirrors stopped working and the interior lights not coming on.
Appreciate it if anyone has any ideas.
1987 928 S4
My power windows stopped working, both windows worked before and they stopped working at the same time, so I don't think it is the motors, relay checks OK, fuse is OK, I have power to the fuse and to the relay, but no power to the switch. I did remove the relay and bridged the 30 to 87 terminal on the relay board but still no power at the switch.
I don't know if this may be related, my instrument gages have been jumping and flashers blinking and also the mirrors stopped working and the interior lights not coming on.
Appreciate it if anyone has any ideas.
I have had a similar problem with windows working intermittently in my 81. My driver side has always worked, but the passenger side only does sometimes. Yesterday, the passenger side decided to work (a friend rolled it down) but once down would not go back up. To add to it, now the driver side does not work. Fuses and relays look fine. Grounds to the circuit board are cleaned. What else might explain intermittent window function?
Also, neither seat controls nor sunroof work.
11-27-2016, 11:18 PM
#10
Nordschleife Master
Well, first off - push the switches and watch the voltmeter. If it moves when you hit the switch, then there is power going to the motor. Either the motor or something in the mechanism is jammed/gummed up.
If not, then the motor isn't getting power. That could be a bad switch or broken wiring. For the windows, I'd suspect the wiring first. Try holding the switch while opening and closing the door. After that, take a look at the switches.
The same thing goes for the seats & sunroof, but I would not suspect the wiring as much as the switches. Also, there's a pretty good writeup on the sunroof in the "New Visitor" sticky. Last page.
If not, then the motor isn't getting power. That could be a bad switch or broken wiring. For the windows, I'd suspect the wiring first. Try holding the switch while opening and closing the door. After that, take a look at the switches.
The same thing goes for the seats & sunroof, but I would not suspect the wiring as much as the switches. Also, there's a pretty good writeup on the sunroof in the "New Visitor" sticky. Last page.
11-28-2016, 10:53 AM
#11
Intermediate
Well, first off - push the switches and watch the voltmeter. If it moves when you hit the switch, then there is power going to the motor. Either the motor or something in the mechanism is jammed/gummed up.
If not, then the motor isn't getting power. That could be a bad switch or broken wiring. For the windows, I'd suspect the wiring first. Try holding the switch while opening and closing the door. After that, take a look at the switches.
The same thing goes for the seats & sunroof, but I would not suspect the wiring as much as the switches. Also, there's a pretty good writeup on the sunroof in the "New Visitor" sticky. Last page.
If not, then the motor isn't getting power. That could be a bad switch or broken wiring. For the windows, I'd suspect the wiring first. Try holding the switch while opening and closing the door. After that, take a look at the switches.
The same thing goes for the seats & sunroof, but I would not suspect the wiring as much as the switches. Also, there's a pretty good writeup on the sunroof in the "New Visitor" sticky. Last page.
11-28-2016, 10:18 PM
#12
Nordschleife Master
You are welcome.
The "Open and close the door" trick will show (or not show) a common failure. The wires going between the door and the body flex every time the door is opened. Eventually they break. It's more common for the driver's side to do this because the door is opened more often.
The "Open and close the door" trick will show (or not show) a common failure. The wires going between the door and the body flex every time the door is opened. Eventually they break. It's more common for the driver's side to do this because the door is opened more often.
