Weak Headlight Motor?
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Melting Slicks
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From: God's Country The Old Dominion
Weak Headlight Motor?
The passenger side headlight on my '04Z would only raise about 3/4 of the way so I raised it the rest of the way with the manual adjuster. I removed the cover and bezel and it raised completely. I reinstalled the cover and bezel and it would only come up 3/4 again. I can't find anything binding. Would a weak motor cause this?
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From: Anthony TX
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The head light motors are controlled by a head light control module. The module senses when the head light motor reaches peak current (fully raised or fully lowered) and it turns the motor off.
The module feeds each headlight with a control signal for up or down. There is a FUSE for each head light motor in the under hood fuse center.
Fuse 4 is for the HDLP MOT LH
Fuse 5 is for the HDLP MOT RH
Get a DC Volt meter and make sure that you have full battery voltage at both of those fuses. There is a test slot on top of the fuse that you can use to read the fuse to chassis ground. Those fuses should be hot at all times. Look for full battery voltage on those test points.
I woulld also pull the fuse and make sure that the blades are clean and fit tight into the fuse slot.
The ground for that module is at G-102 and that is aft of the passemgeds head light assembly on top of the frame. The ground is for both of the headlight motors so, I do not think its the issue unless you are having issues with both motors.. If all that checks out, you may have a bad head light motor OR the module could be bad.
I can send you the schematic if you provide an e-mail to send it to.
The module feeds each headlight with a control signal for up or down. There is a FUSE for each head light motor in the under hood fuse center.
Fuse 4 is for the HDLP MOT LH
Fuse 5 is for the HDLP MOT RH
Get a DC Volt meter and make sure that you have full battery voltage at both of those fuses. There is a test slot on top of the fuse that you can use to read the fuse to chassis ground. Those fuses should be hot at all times. Look for full battery voltage on those test points.
I woulld also pull the fuse and make sure that the blades are clean and fit tight into the fuse slot.
The ground for that module is at G-102 and that is aft of the passemgeds head light assembly on top of the frame. The ground is for both of the headlight motors so, I do not think its the issue unless you are having issues with both motors.. If all that checks out, you may have a bad head light motor OR the module could be bad.
I can send you the schematic if you provide an e-mail to send it to.
Last edited by Bill Curlee; Oct 26, 2018 at 02:26 PM.
Melting Slicks
Joined: Jan 2009
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From: Miami FL
The passenger side headlight on my '04Z would only raise about 3/4 of the way so I raised it the rest of the way with the manual adjuster. I removed the cover and bezel and it raised completely. I reinstalled the cover and bezel and it would only come up 3/4 again. I can't find anything binding. Would a weak motor cause this?
You said you manually raised it from the ¾ point until totally open. It would be good to repeat this, but going from totally closed to totally open, paying extra attention to any difference in required effort around the ¾ point.
Since it works fine with the cover and bezel removed, that makes them good candidates for being the cause of a potential interference.
The way the headlights work is not based on predetermined positions. When the headlight doors open or close and they reach the end of their travel, they press against the corresponding rubber bump stops (provided there's no abnormal interference/binding). As a result the current through the headlight motors increases and that is sensed by the Headlight Door Control Module, which in turns cuts power to the motors.
Last edited by GCG; Oct 25, 2018 at 05:30 PM.
