power window motor help on a 1990 need help
Thread Starter
Safety Car
Joined: Oct 2008
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From: Yucaipa CA
power window motor help on a 1990 need help
Ok, I bought new motors because my passenger side one would move a inch and quit working then work again after a few minutes.
So I plug a new motor into the harness and with the drivers side switch assembly unplugged the passenger side wont work. But when I plug it in and touch the motor against the window regulator it sparks and runs on its own. Then when I use the switch on the passenger door it speeds up and I feel the wires get hot and it stops for a minute.
Could this be the battery drain this car has always had? I don't see any damaged wires anywhere so any of you seen this before on a 1990?
My drivers side widow always works correctly but the passenger side has always done this since I bought this car and has always had the battery drain. basically even if I am not touching the window switch and just touch the motor to the regulator it sparks then the motor runs and switch wires get hot.
I am not really good at electrical but does this sound like the power wires for the motor are grounding? Or since it starts when the drivers side switch is plugged in is that the heart of the problem,
HELLLLLLLLLLLLLLLLLLLLLP!
So I plug a new motor into the harness and with the drivers side switch assembly unplugged the passenger side wont work. But when I plug it in and touch the motor against the window regulator it sparks and runs on its own. Then when I use the switch on the passenger door it speeds up and I feel the wires get hot and it stops for a minute.
Could this be the battery drain this car has always had? I don't see any damaged wires anywhere so any of you seen this before on a 1990?
My drivers side widow always works correctly but the passenger side has always done this since I bought this car and has always had the battery drain. basically even if I am not touching the window switch and just touch the motor to the regulator it sparks then the motor runs and switch wires get hot.
I am not really good at electrical but does this sound like the power wires for the motor are grounding? Or since it starts when the drivers side switch is plugged in is that the heart of the problem,
HELLLLLLLLLLLLLLLLLLLLLP!
Last edited by jeffp1167; Jun 26, 2010 at 08:09 PM.
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
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From: Yucaipa CA
BTW .... when the motor is grounded anywhere and you do touch the switch it works for a second then trips the circuit breaker. Why wouldn't the drivers motor be affected though if this was a battery or ignition feed grounding somewhere?
Everything seems to work normally on the car and it does not blow fuses or fusible links.
One thing I have found weird about the drivers side switch is the switch for the passenger side sits much lower then the drivers switch. Am I dealing with a passenger side switch causing this since the drivers window is never affected or something more serious?
Everything seems to work normally on the car and it does not blow fuses or fusible links.
One thing I have found weird about the drivers side switch is the switch for the passenger side sits much lower then the drivers switch. Am I dealing with a passenger side switch causing this since the drivers window is never affected or something more serious?
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Jeff,
Have you tried an ohm meter on the driver and passenger switch?
Maybe some one else will chime in and help.
Good luck.
Mike
Have you tried an ohm meter on the driver and passenger switch?
Maybe some one else will chime in and help.
Good luck.
Mike
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
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From: Yucaipa CA
I would think the hatch switch to be a switch that just grounds the hatch release. All the other hatch releases work except for this one. I have tried a known working hatch release from the drivers door on the passenger side and no luck. The passenger side switch hooked up on the drivers door pops the hatch so this issue is something else. The door jamb switch also appears to be altered as well, so I am wondering if there is something left of that alarm system causeing the problem.
Petty baffled on this one!
I would think if I infact had a bad electrical issue other things on the car would be affect such as fuses blowing, bulbs popping, fusible links incinerating but the issue seems isolated to the passenger door so I am at a complete loss on this gremlin.
Last edited by jeffp1167; Jun 27, 2010 at 12:20 AM.
Thread Starter
Safety Car
Joined: Oct 2008
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From: Yucaipa CA
Well after looking at the FSM electrical manual it gives a few test light tests. It basically says to check for open in two circuits and if that isn't the problem has to be the switches. It also says the motors have internal circuit breakers that trip if resistance is met involving the motors, regulators etc.
Non of the window motor wiring is tied into anything else in the car and my old window motor does the same thing the new motors do so according to the FSM if no opens are found it has to be the switches.
I will let you all know what the test light does.
Non of the window motor wiring is tied into anything else in the car and my old window motor does the same thing the new motors do so according to the FSM if no opens are found it has to be the switches.
I will let you all know what the test light does.
Le Mans Master
Joined: May 2006
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From: Irvine Ca
wasn't there something about the passenger wires being connected opposite of the driver side??
I read that at one time....not sure if it leads to anything of consequence....just putting this on the table for discussion.
I read that at one time....not sure if it leads to anything of consequence....just putting this on the table for discussion.
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
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From: Yucaipa CA
The fsm says unplug window switches individually and test like that but when I do then the motor won't work at all. I don't know why when the motor touches a ground it runs at a very slow speed on it own then trips a circuit breaker. But even when the passenger side does trip a circuit breaker the drivers window motor always works normally.
I just figured if one 1990 does this surely another has and someone might know the answer. I don't see how a switch can internally short and not have any signs of a problem. I do see a resistor looking thing on the passenger switch though. I am going to look at the wiring in the drivers door a bit later and see if something is damaged.
Le Mans Master
Joined: May 2006
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From: Irvine Ca
I seem to remember the upgrade from Ribbon to scissors said that the passenger wires had to be opposite......so if you have the spade connectors on the motor wrong....then when you touched the motor to ground.....a circuit would be completed.....try to swap the spade connectors and see what happens?? I mean, the worse that could happen is the motor runs backwards or you blow a fuse.
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Thread Starter
Safety Car
Joined: Oct 2008
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From: Yucaipa CA
I seem to remember the upgrade from Ribbon to scissors said that the passenger wires had to be opposite......so if you have the spade connectors on the motor wrong....then when you touched the motor to ground.....a circuit would be completed.....try to swap the spade connectors and see what happens?? I mean, the worse that could happen is the motor runs backwards or you blow a fuse.
Ok I think I found the problem. I did all the FSM test procedures and everything seems to pass doing it the way they say with a test light.
Using the motor I guess for the driver side it shorts when touching to the regulator, however when I use the motor that looks right for the passenger side it doesn't do this.
this is the motor that looks like a match for my passenger side ..... Is the other motor for the drivers side just bad? These are supposed to be new motors or are the two motors wired differently to work only on one side?
Thread Starter
Safety Car
Joined: Oct 2008
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From: Yucaipa CA
I am not sure how to tell the difference between ribbon/scissor regulators but the passenger door (could) have been swapped at sometime since it appears this car had major rearend accident. So it could very well have another year door on it and that is what the cause is.
Thread Starter
Safety Car
Joined: Oct 2008
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From: Yucaipa CA
Well, I took and switched the wires around on the connector for the motor. The passenger side (new) motor just reverses rotation from what it should be. The drivers (new) motor as well as the old passenger motor still short out.
I guess this means one of my new motors is junk and the original passenger side motor is junk as well.
Now being the old motor in the passenger door does exactly what the new motor does (arcing when touched to ground) could this have been the mystery battery drain this car has always had. Basically the battery would be totally dead over night.
I guess this means one of my new motors is junk and the original passenger side motor is junk as well.
Now being the old motor in the passenger door does exactly what the new motor does (arcing when touched to ground) could this have been the mystery battery drain this car has always had. Basically the battery would be totally dead over night.
Le Mans Master
Joined: May 2006
Posts: 9,226
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From: Irvine Ca
Do this, look at the FSM to see if there is a limit relay....something happens when the window reaches it's limits that turn off the power to the motor....."I think"
similar to the relay that cuts the power when voltage feedback spikes when our headlight buckets reach their end.
I'm just guessing..............
similar to the relay that cuts the power when voltage feedback spikes when our headlight buckets reach their end.
I'm just guessing..............
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
Do this, look at the FSM to see if there is a limit relay....something happens when the window reaches it's limits that turn off the power to the motor....."I think"
similar to the relay that cuts the power when voltage feedback spikes when our headlight buckets reach their end.
I'm just guessing..............
similar to the relay that cuts the power when voltage feedback spikes when our headlight buckets reach their end.
I'm just guessing..............
Melting Slicks
Joined: Apr 2003
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From: Red Sox Nation! RI
Jeff, put a voltmeter on the switches or wiring at the motor and see which one is hot and which is ground. You can carefully pull the pins out of the plug and reverse them (as opposed to cutting and splicing)
Thread Starter
Safety Car
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From: Yucaipa CA
If memory serves me right both wires had power with the switch in the nuetral position I can't remember. One of the new motors however workd fine even when it is touched against the regulator.
I've left the battery on the car connected tonight so we will see if it's this motor causing the battery drain or not.
I don't think this is a wiring problem with the car however since two motor do this while the one new motor seems to work normaly.
It is a possibility the used motor is a earlier unit but I tried re-pinning the connector and it did the same thing it was doing before as did one of the new motors. I think one of the new motors has problems and that is why it is doing the same as the old motor.
The FSM directs you to test with a testlight search for reasons of the switch not switching power to raise or lower the window. The car passes all these tests and duplicates everything the fsm mentions.
Thread Starter
Safety Car
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From: Yucaipa CA
Problem has been solved!
Ok after putting this job off because the rivets got to me and replacing them and finding them a big hassle. I came up with as better idea, I left the transmission in place and took the new motor apart and put the electrical stuff onto the old transmission. I cycled the regulator about 30 times and it has worked flawlessly!
Here is the new transmission and old commutator and brush assembly and cap. I basically just put the new cap, commutator, brush assembly on old transmission after cleaning the inside of the old transmission and lubricating it.
easy job takes about 1/2 a motor. You could probably do this job without even removing the regulator ( I think ) motor run really fast up with no load, from bottomed out to top position about 2 1/2 seconds. I will let you all know how it does when lifting the window.
It does not pop circuit breaker anymore though.
Ok after putting this job off because the rivets got to me and replacing them and finding them a big hassle. I came up with as better idea, I left the transmission in place and took the new motor apart and put the electrical stuff onto the old transmission. I cycled the regulator about 30 times and it has worked flawlessly!
Here is the new transmission and old commutator and brush assembly and cap. I basically just put the new cap, commutator, brush assembly on old transmission after cleaning the inside of the old transmission and lubricating it.
easy job takes about 1/2 a motor. You could probably do this job without even removing the regulator ( I think ) motor run really fast up with no load, from bottomed out to top position about 2 1/2 seconds. I will let you all know how it does when lifting the window.
It does not pop circuit breaker anymore though.
Last edited by jeffp1167; Jul 3, 2010 at 09:10 PM.
