'94 Power window problem

[Rhodesplyr]

This evening, I was putting up the driver's door window, and it made a kind of growling sound. Then, the window stopped, almost all the way up, but not quite. When I push the window switch down, I hear a slight click, but the window doesn't move. When I push it up, nothing happens at all. The other windows work normally.

I'm a professional electronics tech, so I understand the circuit. I'm wondering about the "Express" module and if I should check it. I assume it's located somewhere inside the door, correct?

If I need a new motor or regulator, where do you source parts for these nowadays. Online parts places like Advance Auto don't appear to list them.

[aleekat]

Try Rockauto.com

[HotZ28]

Very seldom does the regulator fail on this particular model (1994). This sounds like the switch, or motor is going defunct.

[Rhodesplyr]

Thanks, that's good to know. I'm going to pull the door panel off tomorrow morning--never my favorite job. For tonight, I have a tarp over it in case of rain...

[Rhodesplyr]

I've run into a serious snag with this repair.

I've got the door panel loose except for the weatherstripping section at the top edge. I've had to take the other front door panel off to replace a mirror, and I recall that it seemed like I had to lower the window in order to unhook this strip from the door frame.

This window is 7/8 of the way up. I can't lower it in order to get the door panel loose, and I can't really work on the window mechanism with the door panel in the way.

Any ideas on how to proceed?

Add to this that it's raining outside, and I'm having to do all this under a tarp.

It appears not to be a switch problem. The switch checks out with an ohmmeter.

[Tech II]

The way you check the switch is with a test light....disconnect harness to the motor, and attach a test light to harness....press the switch in both directions, and the light should turn on in each direction...

[Rhodesplyr]

I managed to fix it. The problem was that all four screws that hold the window motor to the gear housing had worked loose and fallen out. The motor brushes appear to have gotten cracked when it came apart and the replacement was only $36, so I elected not to try to repair the original motor assembly.

I was trying to remove the three nuts that secure the motor with the door panel still attached, since I couldn't get it to come off, but I accidentally broke the panel loose from the window weatherstripping, which was VERY firmly stuck in place. When I put the door back together, I put a bead of weatherstrip adhesive along the edge and popped the main door panel back into the groove on the weatherstrip.

And, yes, the window will go up and down by hand if you remove the motor assembly--for anyone reading who hasn't done this before. The motor looked like it would probably have lasted for as long as I'll own this car--had its housing not come unscrewed.

To Tech II: how is a test light different from a professional Fluke Multimeter on an Ohms setting? I repair organs and guitar amps and use the Fluke every day to test for connection integrity.

[Tech II]

I'd rather test an electrical circuit with power, rather than a static test....just my preference......especially when modules are involved.....have seen guys test strong current circuits with voltmeters....ALL THEY ARE READING IS POTENTIAL VOLTAGE....this leads to misdiagnosis...voltmeter reads 12 volts, but a test light might be dim due to a voltage drop in the circuit due to a bad connection....one reason to work with a live circuit, rather than a static test..

If the screws that held the motor to the regulator came loose, it's because the motor was already replaced, and whoever tightened the screws did not do a good job....original motors are pop riveted to the regulator.....

Sounds like you were lucky......those old models sometimes had a strong clock spring, attached between the motor and the regulator....if it had one, when you removed the retaining screws, the motor could have come flying around and possibly caught a finger or two...

[Rhodesplyr]

Originally Posted by Tech II

I'd rather test an electrical circuit with power, rather than a static test....just my preference......especially when modules are involved.....have seen guys test strong current circuits with voltmeters....ALL THEY ARE READING IS POTENTIAL VOLTAGE....this leads to misdiagnosis...voltmeter reads 12 volts, but a test light might be dim due to a voltage drop in the circuit due to a bad connection....one reason to work with a live circuit, rather than a static test..

These guys probably weren't professional electronics techs who test for bad switches and connections all the time--in circuits that are much more complex than this one. I tested the switch contacts directly for contact resistance. I even have a special low-Ohms meter that I often use to check for switch contact and ground integrity. Ohm's Law is Ohm's Law, and I understand if I'm reading voltage, current, or resistance. In this case, I was testing for resistance, not voltage, and the switch works, so, apparently, I wasn't wrong :-)