Power Window Works Once Then Quits

[Sompin2do]

Driver side window on my 94 GT will work one time after I start the engine and then quits after that. Any ideas would be greatly appreciated.

Thanks
Mike

 

[chaos254]

its either the switch or the bushings in the motor. the bushings only cost like $5 to fix, the switch is around $16. So either way it won't be that expensive to fix.

 

[HISSIN50]

If you try the windows after a little bit (but not restarting), does it come back? Do you see the voltmeter dip when you hit the button? If so, does the voltmeter pop back up after a minute?
The circuit breaker for the windows might be blowing (the cause of which is likely in the window motor itself). I'd pull the door panel and do some testing at the motor with your meter.

Good luck.

 

[Sompin2do]

I got the motor out and the bushings look okay I guess. One of them is cracked but they still have their shape.
Voltmeter does dip when hitting the switch but window doesn't move. Sound like a bad motor or bad switch?

Thanks

 

[Sompin2do]

Now I'm lost. Before I bought a new motor I swapped the switches on the driver side and both operate the passenger window fine.
So I went and bought a new motor for the driver side. I connected the new motor to the plug before bolting it up and I got nothing. Passenger window still operates okay. Help????

Thanks
Mike

 

[HISSIN50]

The use of a voltmeter is helpful.

You noted that you saw your stock voltmeter dip while hitting a switch. That's always a good indicator that a switch is functional (the dip in voltage is the switch allowing power to reach a component, whether or not the component functions properly).

At this point, I'd check I/O voltages at the driver's side switch. You could also test at the motor directly.

Good luck.

 

[Sompin2do]

When you say "check the I/O voltages at the driver side switch" I guess I'm not following...
If I swapped the 2 switches around and both operate the passenger window, doesn't that mean the switch is okay?

Can you instruct me on testing at the motor directly? Are you saying to use the leads from my meter on the plug coming from the switch?

Thanks again
Mike

 

[HISSIN50]

When you say "check the I/O voltages at the driver side switch" I guess I'm not following...
If I swapped the 2 switches around and both operate the passenger window, doesn't that mean the switch is okay?

Can you instruct me on testing at the motor directly? Are you saying to use the leads from my meter on the plug coming from the switch?

Thanks again
Mike

I/O = voltage in and out.

I agree that swapping switches should indicate that both switches are ok.

To test the motor itself is easy. You access it (remove the door panel). Disconnect it from the body harness. You can use a fused jumper wire from the battery and a jumper ground wire to see if the motor moves. Reversing the leads reverses the direction of the window motor's output shaft. Be real careful of the regulator and other moving parts inside the door panel.

To test the circuit bringing power to the motor, you do as you outlined. Put each meter lead into the back of the motor's e-connector (backprobe the connector) and see what the meter reads while hitting the button.

In case it helps, here's a neat DMM usage guide. I'll try and remember to check the window schematics later on and see what you're dealing with exactly (they're 5 wire reverse polarity IIRC).

Good luck.

 

[Sompin2do]

Okay, I'm starting to follow you. I actually went and bought a new motor when I took the old one apart and found the bushings okay. I spliced the new motor in without bolting it up, but still got nothing.

Since I've already got the old motor out I can just test it at the battery?

Then I'll check the circuit bringing power to the motor. Thanks for the link to the user guide.

Mike

 

[HISSIN50]

Okay, I'm starting to follow you. I actually went and bought a new motor when I took the old one apart and found the bushings okay. I spliced the new motor in without bolting it up, but still got nothing.

Since I've already got the old motor out I can just test it at the battery?

Then I'll check the circuit bringing power to the motor. Thanks for the link to the user guide.

Mike

Hey Mike,

You definitely can bench test the motor using the battery - that's how I do it. Please do use a fuse of some sort (the stock circuit protection is a 20 amp circuit breaker as I recall. I'd mimic that or use a 20 amp slow-burn fuse).

Since the new motor doesnt work, it sure looks like a wiring issue to the motor. I'd bet when you put your meter on the PW motor connector (in the door), you're not seeing anything. I'd go back to the switch and ensure power is going into the switch. Then test the I/O's at the switch to see what's not happening. I'd have to look at a diagram to spit out wire colors and such.

 

[Sompin2do]

Okay, both motors worked fine at the battery. I made a mistake earlier when I said I noticed the stock voltmeter dip, it doesn't. Meaning that with the key on I can press the switch for the passenger window and the stock volmeter dips and dome light flickers. That doesn't happen at all with the driver side.

Next I used a meter on the back of the switch block touching the black to black and red to yellow. When I press the switch to the up position the meter comes up, the same as on the passenger side.

I can get the same results at the motor connector on the door touching the red to yellow and grounding to bare metal.

Should I be getting anything off the red wire?

 

[HISSIN50]

Ok, you're doing good here. Now Mike, I just checked schematics. Did you know there are 6 configurations of how these cars were wired up? Do you know if you have the one-touch power window feature? You should see the black box for it in the rear of the driver door IIRC. If you don't, that's one less item to consider.

Assuming you have one-touch, the red wire egresses the One-touch module and goes to the motor. You should see 12 volts at that wire if yellow shows ground, or vice verse (depending upon if you're rolling up or down).

If red doesnt do anything, the next step backwards appears to be whi/blk, going from the driver switch to the black one-touch box.
Ensure the One Touch box has 12 accessory volts from LB/Blk.

One last thing to check is that all grounds are good. Every pure black wire I've seen is a continuous ground. There's one on the One-touch module and a couple for each window switch IIRC.

I've been assuming you have a coupe and trying to generalize the wiring to include different forms of trim that matter. If you know, post if you have:

-a vert or coupe.
-factory remote keyless.
i-lluminated entry nit but no keyless entry.
-anti theft but no remote entry.
-no remote keyless or anti theft

(those are all items which change the wiring pathways slightly).

 

[Sompin2do]

WOW! SIX?!!?

I do have the one-touch feature. Since the motor checked out I put it back in the car and connected the plug.
Yesterday when I started taking things apart I remember feeling the one-touch module but didn't even consider that as a possible problem. I'll go see if I can follow your instructions for that.

My car is:
A coupe
Factory remote keyless.

Thanks SO much for taking the time to help me with this.

Mike