Another Power window?
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Intermediate
Joined: Aug 2006
Posts: 25
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From: Fredericksburg, VA
Another Power window?
Wife comes home and the drive's side window will not go down. So, I search the site and I think (guessing) I have it down to the relay. Heres the steps I have taken so far, passenger side works fine, up/down no issue. I took apart the switch and broke out the volt meter. 12v going out the proper line from the switch when up / down is pressed. Took the door panel off and this is where I might be missing. Disconnected the plug from the motor, from what I understand, I should have 12v coming thru one of the two wires depending on the up/down switch. Put the volt meter to ground and the positive side in each pin, only get power on the up side. Zip on the down pin. All wires under the dash are originally wrapped, so the next step would be the relay? Does the relay have that much 'control' of each window's operation? Any suggestions or direction is appreciated.
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From: Phoenix AZ
On <90 models the relay does nothing related to the switching of individual windows - it only controls the power switching to all windows (its what allows the windows to operate until you open a door - that is its only function). So if one window or sunroof works that rules out the relay.
Its most likely the switch - you must test switch operation with the motor connected... often they will appear to work fine with no load - add the load and all things go to hell...
Both motor connections should be driven to 0v normally - actually grounded not just floating - so test for 0v and if found check for ohms to ground - should be ~0 ohms. When you engage the switch (DMM back to volts) you should see 12 on one wire for up and 12v on the other wire for down.
Also test the red wire feeding the switches - make sure its stays at approx 12v regardless what you do with the switches.
Try swapping the motor connections - now press the switch up - the window should now go down if it does and won't go back up its one direction of the switch that is faulty only. Switches can be cleaned - search for details.
Sometimes its a mechanical switchplate clearance issue only....
Alan
Its most likely the switch - you must test switch operation with the motor connected... often they will appear to work fine with no load - add the load and all things go to hell...
Both motor connections should be driven to 0v normally - actually grounded not just floating - so test for 0v and if found check for ohms to ground - should be ~0 ohms. When you engage the switch (DMM back to volts) you should see 12 on one wire for up and 12v on the other wire for down.
Also test the red wire feeding the switches - make sure its stays at approx 12v regardless what you do with the switches.
Try swapping the motor connections - now press the switch up - the window should now go down if it does and won't go back up its one direction of the switch that is faulty only. Switches can be cleaned - search for details.
Sometimes its a mechanical switchplate clearance issue only....
Alan