Electric Window Woes

Okay folks, I'm stumped need some help.

My front passenger window is driving me insane. I went wheeling about a month ago and couldn't get the window to roll back up. I ended up disconnecting it from the regulator and taping it up for the time being. Anyways, I ended up breaking the old motor while trying to diagnose the issue (broke a brush). Today I got my brand new motor/regulator in the mail and went to go install it.

I can roll the window down, but not up (even with the window disconnected). I plugged the motor into another door and it will go up and down no problem, so the motor is fine. I then moved on to check the connection, using a voltmeter I checked the power going through the connection. I get 12V (11.7_) one way, and negative when moving the motor the other direction; so that all appears normal. Out of curiosity I even swapped the wires around inside the connector, and sure enough the motor will go up but not down now.

I looked through the FSM for help, but there are no diagnostic routines for a motor going one way and not the other. But from what I understand there are four circuits that control the window motor in pairs, one pair ground while the other powers. I don't know where to look for these or even how to begin checking them etc. Any help would be awesome.

I don't have my FSM with me for referance, but my guess is that you have a bad switch.
There are diodes in the window switches and one maybe open.
This is all from (not so good) memory! you'll have to study the schematic to see if this could be the problem.
Good luck

Does the switch on the drivers door make it work?

All the motor does is turn one way or the other depending on polarity. You might have a short to ground that is only appearing when power is applied to that wire, and not showing up when that same wire is used for ground.

ehall said:

Does the switch on the drivers door make it work?

All the motor does is turn one way or the other depending on polarity. You might have a short to ground that is only appearing when power is applied to that wire, and not showing up when that same wire is used for ground.

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How/where would I check for the a faulty ground?

FallibleXJ said:

Out of curiosity I even swapped the wires around inside the connector, and sure enough the motor will go up but not down now

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When you did this, did the window go up with the switch in the down position?

NEWYXJ said:

When you did this, did the window go up with the switch in the down position?

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yup

I have a full set of switches if you need them.

FallibleXJ said:

yup

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Then I would think the wiring is good.
The polarity switching for up and down is controled by diodes. I think I may have miss wrote above, the diodes may all be in the drivers master window switch only and not in the passenger switch.

One other thing to consider, you may read the correct voltage across a bad connection, but a heavily corroded wire will not let enough current flow to power the motor.......learned this AGAIN on my boat this weekend.

FlexdXJ said:

I have a full set of switches if you need them.

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Could you PM me with a price shipped to 14623?

tugalo said:

One other thing to consider, you may read the correct voltage across a bad connection, but a heavily corroded wire will not let enough current flow to power the motor.......learned this AGAIN on my boat this weekend.

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The connectors appear to be clean (nice shiny copper)

NEWYXJ said:

Then I would think the wiring is good.
The polarity switching for up and down is controled by diodes. I think I may have miss wrote above, the diodes may all be in the drivers master window switch only and not in the passenger switch.

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The window does the same thing from the driver's side switches, where would I look to investigate a faulty diode?

FallibleXJ said:

The window does the same thing from the driver's side switches, where would I look to investigate a faulty diode?

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FSM and a multi-meter with diode testing.

Okay well all of the switches seem okay (I checked them against the continuity charts in the FSM)

Next?

tugalo said:

One other thing to consider, you may read the correct voltage across a bad connection, but a heavily corroded wire will not let enough current flow to power the motor.......learned this AGAIN on my boat this weekend.

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This is my bet. Try measuring for voltage while the motor is plugged in and operating - if you see a negative voltage in about the right range and the motor won't move I don't know what the problem is, but my bet is that when the motor is plugged in and refusing to move you will measure a very small voltage indicating a bad wire somewhere. From there it's just "divide and conquer" with the meter and FSM - go upstream a bit, check again, if measurements seem good, move downstream again, continue until you have narrowed the problem down to a single harness, wire, component, or splice.

Remember that your multimeter has an input resistance of around ten million ohms, while the motor has only a few ohms resistance. Therefore the meter draws so little current that even a high resistance corroded connection will not exhibit a significant voltage drop.

Where is the bulk of all of these wires? Im assuming in the passenger side junction area

I have not been much help. I will check this thread next week when I get back to my FSM.
Hopefully the problem is resolved by then.

Well unfortunately I seem to have fubared my multimeter (cheap Harbor Freight one). It refuses to pick up anything anywhere.

I had trouble with a couple windows going down but not up. It ended up being cracked wires in the drivers door pass-through. Apparently the power to switches is routed from the driver's master switch. Up and down power was seperate from what I remember. I went throught the whole hassle of replacing switches and it wasn't it.

troy said:

I had trouble with a couple windows going down but not up. It ended up being cracked wires in the drivers door pass-through. Apparently the power to switches is routed from the driver's master switch. Up and down power was seperate from what I remember. I went throught the whole hassle of replacing switches and it wasn't it.

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Did you just pull off the rubber cover and check them out?

You may be able to do that, but I actually disconnected the wiring harness and took it out so I could work with it on the work bench. I'm not sure how the rubber boot is held in place, that may be an easy attempt for diagnosing your problem. That is exactly where my wires were bad.

My wires seemed really brittle. I'm in a cold climate, so it may have been from seasonal changes, etc. Could just be cheap wiring.

Update: Found the problem

After a few hours yesterday with a multimeter I found the problem. A wire had in fact broken in the driver's door hinge. Thanks for the help all!