electrical gremlin du jour.
07-19-2016, 11:49 AM
#1
Rennlist Member
Thread Starter
electrical gremlin du jour.
I have a electrical problem that I need to research in my 1988 928 S4 (maybe this should be a sticky thread for everyone).
1. power door locks won't activate from doors (switch or key). However they do activate from dash.
2. power windows are always active with or without the key, no matter how many times the door is open and closed.
I was thinking there was a problem in the window relay that stays active after the car is shut off until the door is opened. However, not sure why the door locks are disabled.
Thoughts are appreciated, as well as, sources for that window relay.
1. power door locks won't activate from doors (switch or key). However they do activate from dash.
2. power windows are always active with or without the key, no matter how many times the door is open and closed.
I was thinking there was a problem in the window relay that stays active after the car is shut off until the door is opened. However, not sure why the door locks are disabled.
Thoughts are appreciated, as well as, sources for that window relay.
07-19-2016, 02:23 PM
#2
Rennlist Member
Can't help with locks but had same issue with the windows in my 87S4, they worked regardless of key in ignition or not.
Do all your interior lights work correctly? After I fixed my interior lights the window issue was resolved. Also check your door pin switches along with rear hatch switch as they are part of the interior light circuit.
Do all your interior lights work correctly? After I fixed my interior lights the window issue was resolved. Also check your door pin switches along with rear hatch switch as they are part of the interior light circuit.
07-19-2016, 03:46 PM
#4
Rennlist Member
Thread Starter
Good call on the interior lights. I'll check all of them.
07-27-2016, 01:32 AM
#5
Rennlist Member
Thread Starter
Found it. Turned out to be a faulty relay for power windows. Swapped it out and everything is back to normal.
11-27-2016, 11:44 AM
#6
Intermediate
I have had a 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.
Also, neither seat controls nor sunroof work.
11-27-2016, 04:58 PM
#7
Chronic Tool Dropper
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Since the motor runs on the right side in one direction, the motor itself is most likely OK. The circuitry on your '81 depends on reversing the polarity of the current to the motor, all managed in the switch itself. The switches suffer from age-related deterioration as the grease inside turns to wax/soap and prevents the contacts in the bottom from working correctly.
Repair options include removing and disassembling the switches (do both, one at a time), cleaning all the old grease and junk out of the bottom, and reassembling. The original grease was a fairly standard #2 grease. Better options now include Vaseline or one of the better non-metallic synthetic greases available, like Mobil-1 or Redline chassis and bearing greases. "Dielectric grease" would work, a non-metallic silicone grease. The contacts inside are "connected" by a sliding bar that's moved around by the legs under the rocker. Note that the rocker is also subject to casual physical abuse when hands or elbows use the switches as a fulcrum point for entry and exit.. So physical damage is common.
You can buy good replacement switches from any of our regular 928-specific sponsor-suppliers. Look at 928 International, 928srus, and our forum sponsor 928 Specialists. Non 928-specific suppliers may also have the switches available.
The switches are accessible by removing the side covers on the console. There are pigtails with multi-pin connectors forward in the console, then the switches come out from the top. Mark the connectors with tape so you can get them back in to the right places. You'll want to clean the sunroof and rear wiper switches (if you have them) at the same time.
-----
There are significant differences between the series of cars. This thread starts out looking at S4 window switch functions. Your '81 power window motor circuitry/wiring is different, so deserves a separate thread. Don't be shy about posting a thread of your own, with a subject title perhaps more specific to the problem you are researching. It makes future searches by others a lot easier.
Welcome to the group!
Repair options include removing and disassembling the switches (do both, one at a time), cleaning all the old grease and junk out of the bottom, and reassembling. The original grease was a fairly standard #2 grease. Better options now include Vaseline or one of the better non-metallic synthetic greases available, like Mobil-1 or Redline chassis and bearing greases. "Dielectric grease" would work, a non-metallic silicone grease. The contacts inside are "connected" by a sliding bar that's moved around by the legs under the rocker. Note that the rocker is also subject to casual physical abuse when hands or elbows use the switches as a fulcrum point for entry and exit.. So physical damage is common.
You can buy good replacement switches from any of our regular 928-specific sponsor-suppliers. Look at 928 International, 928srus, and our forum sponsor 928 Specialists. Non 928-specific suppliers may also have the switches available.
The switches are accessible by removing the side covers on the console. There are pigtails with multi-pin connectors forward in the console, then the switches come out from the top. Mark the connectors with tape so you can get them back in to the right places. You'll want to clean the sunroof and rear wiper switches (if you have them) at the same time.
-----
There are significant differences between the series of cars. This thread starts out looking at S4 window switch functions. Your '81 power window motor circuitry/wiring is different, so deserves a separate thread. Don't be shy about posting a thread of your own, with a subject title perhaps more specific to the problem you are researching. It makes future searches by others a lot easier.
Welcome to the group!
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11-28-2016, 10:52 AM
#8
Intermediate
Since the motor runs on the right side in one direction, the motor itself is most likely OK. The circuitry on your '81 depends on reversing the polarity of the current to the motor, all managed in the switch itself. The switches suffer from age-related deterioration as the grease inside turns to wax/soap and prevents the contacts in the bottom from working correctly.
Repair options include removing and disassembling the switches (do both, one at a time), cleaning all the old grease and junk out of the bottom, and reassembling. The original grease was a fairly standard #2 grease. Better options now include Vaseline or one of the better non-metallic synthetic greases available, like Mobil-1 or Redline chassis and bearing greases. "Dielectric grease" would work, a non-metallic silicone grease. The contacts inside are "connected" by a sliding bar that's moved around by the legs under the rocker. Note that the rocker is also subject to casual physical abuse when hands or elbows use the switches as a fulcrum point for entry and exit.. So physical damage is common.
You can buy good replacement switches from any of our regular 928-specific sponsor-suppliers. Look at 928 International, 928srus, and our forum sponsor 928 Specialists. Non 928-specific suppliers may also have the switches available.
The switches are accessible by removing the side covers on the console. There are pigtails with multi-pin connectors forward in the console, then the switches come out from the top. Mark the connectors with tape so you can get them back in to the right places. You'll want to clean the sunroof and rear wiper switches (if you have them) at the same time.
-----
There are significant differences between the series of cars. This thread starts out looking at S4 window switch functions. Your '81 power window motor circuitry/wiring is different, so deserves a separate thread. Don't be shy about posting a thread of your own, with a subject title perhaps more specific to the problem you are researching. It makes future searches by others a lot easier.
Welcome to the group!
Repair options include removing and disassembling the switches (do both, one at a time), cleaning all the old grease and junk out of the bottom, and reassembling. The original grease was a fairly standard #2 grease. Better options now include Vaseline or one of the better non-metallic synthetic greases available, like Mobil-1 or Redline chassis and bearing greases. "Dielectric grease" would work, a non-metallic silicone grease. The contacts inside are "connected" by a sliding bar that's moved around by the legs under the rocker. Note that the rocker is also subject to casual physical abuse when hands or elbows use the switches as a fulcrum point for entry and exit.. So physical damage is common.
You can buy good replacement switches from any of our regular 928-specific sponsor-suppliers. Look at 928 International, 928srus, and our forum sponsor 928 Specialists. Non 928-specific suppliers may also have the switches available.
The switches are accessible by removing the side covers on the console. There are pigtails with multi-pin connectors forward in the console, then the switches come out from the top. Mark the connectors with tape so you can get them back in to the right places. You'll want to clean the sunroof and rear wiper switches (if you have them) at the same time.
-----
There are significant differences between the series of cars. This thread starts out looking at S4 window switch functions. Your '81 power window motor circuitry/wiring is different, so deserves a separate thread. Don't be shy about posting a thread of your own, with a subject title perhaps more specific to the problem you are researching. It makes future searches by others a lot easier.
Welcome to the group!
I was, indeed, being a bit shy about starting my own thread, but I will in the future. THanks for the advice and the welcome!
11-28-2016, 01:15 PM
#9
Electron Wrangler
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Seats are almost certainly a separate problem from the windows. Passenger window was likely just a switch issue when everything else worked, now nothing works this may be a separate problem also.
Try wiggling the ignition switch in accessory mode and see if the drivers window starts working...? if so you have an ignition switch problem - replace the electrical part.
You probably still also have a passenger window switch issue - best way to confirm is to swap the switches between driver & passenger side - the switch connectors are in the console passenger side near the back of the radio - take off the carpeted side panel & trace the wires from the switches - just swap the connectors.
Alan
Try wiggling the ignition switch in accessory mode and see if the drivers window starts working...? if so you have an ignition switch problem - replace the electrical part.
You probably still also have a passenger window switch issue - best way to confirm is to swap the switches between driver & passenger side - the switch connectors are in the console passenger side near the back of the radio - take off the carpeted side panel & trace the wires from the switches - just swap the connectors.
Alan
11-28-2016, 01:18 PM
#10
Intermediate
Seats and sunroof are almost certainly a separate problem from the windows. Passenger window was likely just a switch issue when everything else worked, now nothing works this may be a separate problem also.
Try wiggling the ignition switch in accessory mode and see if the drivers window starts working...? if so you have an ignition switch problem - replace the electrical part.
You probably still also have a passenger window switch issue - best way to confirm is to swap the switches between driver & passenger side - the switch connectors are in the console passenger side near the back of the radio - take off the carpeted side panel & trace the wires from the switches - just swap the connectors.
Alan
Try wiggling the ignition switch in accessory mode and see if the drivers window starts working...? if so you have an ignition switch problem - replace the electrical part.
You probably still also have a passenger window switch issue - best way to confirm is to swap the switches between driver & passenger side - the switch connectors are in the console passenger side near the back of the radio - take off the carpeted side panel & trace the wires from the switches - just swap the connectors.
Alan