All four window failure, have no clue...

[mOnkey fArgo]

Hey folks,
So I have this very strange issue. A couple of weeks ago I was rolling up both the passenger and driver side windows at the same time. Both were traveling slower than usual. The passenger window made it all the way up and the driver stopped four inches from the top. Now all windows do not roll up or down. So I began my troubleshooting process. I checked, tested and replaced fuses, auto reset fuses, relays and the master switch in the console. The master switch was tested in another KJ and worked without issue and "their" known working switch did not work in my jeep. With a multimeter I tested throughout the window system. Found that I had 12 volts (or 13+ when running) at the fuse, breaker, and master switch. But at the driver side window regulator, 3.3 volts and at the other three window regulators 1.1 volts. I pulled carpet, cleaned all the system grounds. I have even hooked the driver regulator to direct power, works as expected. The master switch illuminates as expected until you actuate it. Then the lights go dark and in a minute or so they re-illuminate. I am at a loss. I took it into Jeep(when I got my hitch installed) and no body codes were present. Any ideas? I'm at wits end. Please help!

 

[kage860]

Sounds like a ground somewhere? Maybe park it in a heated garage and try it after everything dries out.

 

[belvedere]

I think you have a bad connection in the power feed. You say you have 12V+ at the fuse, switch, etc, but I am guessing this is unloaded. Put your voltmeter at one of these points, and then hit one of the window switches. If my theory is right, the voltage will drop. Let us know.

 

[mOnkey fArgo]

I try to hit the connections with a voltmeter and let you guys know. The garage maybe a bit of a tricky one as I'm in the service and Barracks are a bit lacking.

 

[van462]

Why not use the auto hobby shop on base?

 

[wheeee32]

Why not use the auto hobby shop on base?

That's what I usually do if I can't do it at a friends garage.

 

[mOnkey fArgo]

I have made several trips, working on it myself as well as looping in the guys there. Hence how I've gotten as far as I have. I tested the leads at the switch again as suggested and the voltage does drop out. Any thoughts on what source I need to clean up. All other systems working as expected.

 

[uss2defiant]

if I read your post correctly, you tested the switch in another KJ.
Did you test the window regulator in another KJ?

 

[mOnkey fArgo]

I did not test the regulator with another jeep as that would be a very involved process. However, I did connect the regulator directly to the battery with leads and I was able to roll the window all the way up (down first until I flipped the leads). The regulator seemed to work without issue like that.

 

[belvedere]

I tested the leads at the switch again as suggested and the voltage does drop out.

All I can say is to keep going back. I would test at the fuse/breaker next.

 

[profdlp]

...I did connect the regulator directly to the battery with leads and I was able to roll the window all the way up (down first until I flipped the leads). The regulator seemed to work without issue like that.

If the regulator works like that then your only question is to find where you're losing the voltage along the way.

 

[uss2defiant]

I did not test the regulator with another jeep as that would be a very involved process. However, I did connect the regulator directly to the battery with leads and I was able to roll the window all the way up (down first until I flipped the leads). The regulator seemed to work without issue like that.

so what do you mean when you mentioned 3.3V and 1V? Was that the voltage out from the connector to the window regulator?

 

[mOnkey fArgo]

so what do you mean when you mentioned 3.3V and 1V? Was that the voltage out from the connector to the window regulator?

Exactly, I disconnected the harness at the regulator. Tested the voltage with a digital multi-meter at the vehicle side of that connection. Driver door showed 3.3 positive or negative voltage depending on whether I was rolling up or down the window via the console window switch cluster. The remaining windows, using that same method, showed 1.1 positive or negative respectively.

 

[Billwill]

Exactly, I disconnected the harness at the regulator. Tested the voltage with a digital multi-meter at the vehicle side of that connection. Driver door showed 3.3 positive or negative voltage depending on whether I was rolling up or down the window via the console window switch cluster. The remaining windows, using that same method, showed 1.1 positive or negative respectively.

You need to do these voltage tests with every connector connected.
Piece the insulation on the wires with a pin or sewing needle so as to touch the copper inside and place your meter leads on the pins.

Once you have finished doing this you can seal up the pinholes with some glue!

 

[uss2defiant]

just looking through the wiring diagram, it seems to me that it should be 12V to the window regulator. The same as it should be when you tested them directly with 12V.

3 and 1 volts seem to indicate some issues. I have no idea where the 3 and 1 volts are coming from.
you probably need to do more digging around with the DMM at the switch end and at the harness end to the window regulator.

Probably bad wiring or bad connection.

 

[miltonwaddums]

Sounds like a bad body control module to me. (But the absence of codes doesn't jive.) I'm thinking that maybe drawing the current to roll both up at the same time may have blown a weak cap or weak transistor on the BCM board. Perhaps swap the bcm out with your buddies and retest?