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Passenger power window only goes down. New motor.

jogirob

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Here's a strange one. I guess by coincidence the old motor only functioned one way (tested it when I pulled it out). I replaced the motor and now the window goes up and down when power is applied directly. However if I do either passenger side or driver side switches, it will only go down. This is the passenger side window.
In the morning I'll stick a test light to the harness where it connects to the new motor's pigtail and see if I get anything on the switch UP position. Off the top of anyone's head any idea what it could be? Would a bad window lift safety relay cause this? Driver side functions normally.
 
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can you post a schematic?
when you bench test the motor i'm assuming you are switching the leads to test for reserve operation correct?
without seeing a schematic and using more modern vehicles as a reference i'd say you have a broken lead most likely in the jamb where the harness flexes upon door opening and closing
 
Most likely the switch or connection at the switch connector. I installed relays for my power windows, they take the high current load out of the switches/switch connectors.
 
Still working on getting some good schematics. Here's a few more tests I did that makes me believe I have a short before the window switch on the passenger side door.

Probed the back of the window motor connectors. On window down I get voltage on one lead (pink+black) and not the other (purple+white). Window goes down as normal. On window up I get voltage on both leads and the window goes nowhere. I did a continuity test between purple+white lead and chassis and I get a normal no continuity reading. Continuity tests between pink+black and chassis *does* show continuity.
I cracked open the switch backing and did some continuity tests between pink+black and it shows continuity with the solid purple wire. Purple+white shows continuity with solid pink.

Solid pink and solid purple are from the driver side switch most likely. Striped pink and striped purple wires connect from the passenger window switch to the passenger motor. There's a yellow wire that provides the power source.

I tried disconnecting all wires from the passenger switch other than the power source + the striped passenger side wires hoping to bypass the short but I just got no function at all :-/
 
It might be your drivers side switch? The issue is all the motors ground through the drivers switch. The switches, in the un-pressed condition connect the top and bottom studs on each side so current can pass through them. This is how the drivers side can control the motors. Pressing the drivers switch will break one side of the pass-through from normally grounded, and apply the power to one of the connections (depending if up or down.) that power flows through to the other (single) window switch to the motor, then back from the motor through the single switch, and back through the drivers door quad switch and then back to ground.
On the passenger door (or the other single switches) pressing that switch breaks the through connection and takes the power at the center pin (Yellow wire) and sends it out to the motor, but the return path still flows back through the single switch and through the window switch on the drivers side to get back to ground.
 
Here's a 68 from FSM

2018-09-16 17.19.54.jpg
 
Could be 2 bad switches also?
 
Adding the relays is a good upgrade. Everything grounds through the relays, and they take the high current connections off the switches.
I added the relays to my car around 2000 because none of the windows worked when I got the car. The ground connector on the drivers switch was broken off. With the relays, I no longer need that ground connection, and all the windows work now.
 
On the passenger door (or the other single switches) pressing that switch breaks the through connection and takes the power at the center pin (Yellow wire) and sends it out to the motor, but the return path still flows back through the single switch and through the window switch on the drivers side to get back to ground.
Thanks for the detailed explanation. This makes perfect sense as to why it wouldn't work at all after I removed the 2 driver side wires from the passenger side switch.
I found this thread to help out with that relay install http://board.moparts.org/ubbthreads/ubbthreads.php/topics/142362/2.html . Need to ensure I get my switches cleaned out good first...at least I'm hoping a good scrubbing is all they need.
 
On the passenger door (or the other single switches) pressing that switch breaks the through connection and takes the power at the center pin (Yellow wire) and sends it out to the motor, but the return path still flows back through the single switch and through the window switch on the drivers side to get back to ground.

20180917_212348.jpg
 
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Using the above quote as basis for my own n00b switch functionality test I did the following: Disconnected all plugs leading out of the driver side switch. I connected one multimeter lead to the passenger & driver side window wires and ground output wires on one side, and on the other side I probed the back of the switch where the posts protrude.

They all show continuity with each other except for the pink wire that leads to the passenger window switch. Pink only showed continuity with itself. While my meter showed a resistance of about .6-.8 for all. I got no continuity (1) for pink until I flipped one of the toggle switches to the up (or was it down?) position. I'd get a funky resistance reading of around 50 ohms. When I released the switch, resistance went down to 35ish and stayed there for the pink wire. When I toggled the switch to the down(or was it up?)position I'd get no continuity (1) once again.

So this means it's a physical problem with the window up switching mechanism right?

20180919_192159.jpg
 
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I build/put together essentially a plug and play power window relay kit for a lot of customers. Works great and saves those expensive OEM switches for the load.

I had an ad on here and over at FABO. About $300 for all 4 windows.
 
*Solved*
Problem pinpointed to the switch mechanism itself. A couple light taps to the driver side switches fixes the issue momentarily. Still replacing the switch + backing & wiring for good measure.
 
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