Headlight problem, new user
Thread Starter
4th Gear
Joined: Aug 2010
Posts: 4
Likes: 0
From: SIOUX CITY IOWA
Headlight problem, new user
My 91 convertable is having headlight problems, I replaced the headlight module a year ago and everything was fine till the other day when the left headlight wouldnt raise anymore. I tested all the wires and also ran 12v right to the motor and it works. I got another headlight module and pluged it in and it worked once then same problem as before. I am only getting th 12v to the right side, any ideas what I should look at or what could be taking this module out? I am lost!!!! HELP PLEASE!!
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Read this thread..
http://forums.corvetteforum.com/c4-t...air-w-pic.html
Before you click over there. That thread got convoluted with two generations of light assemblies. There is an old design and a new one.
Yours needs the new advice that calls for new bushings to be replaced in your system.
One thing that is more in tune with your problem is the voltage feedback. If the motor is weak, the module reads a voltage spike and turns off the power........you may need new brushes or a new wound motor versus just new bushings etc.
http://forums.corvetteforum.com/c4-t...air-w-pic.html
Before you click over there. That thread got convoluted with two generations of light assemblies. There is an old design and a new one.
Yours needs the new advice that calls for new bushings to be replaced in your system.
One thing that is more in tune with your problem is the voltage feedback. If the motor is weak, the module reads a voltage spike and turns off the power........you may need new brushes or a new wound motor versus just new bushings etc.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Doesn't sound like you are having problems with the bushings, more likely with the ground at the module. The relays in the module reverse the polarity to either raise or lower the H/Ls. Two bad modules in a row is unlikely, so I would check the ground. It might take a FSM to do the diagnostics properly.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
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Team Owner
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Order your FSM's online at Ebay. Often there are bargains to be found. I purchased the complete, two-volume set for my '92 in very gently used condition for under $50 bones (shipping included).
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
My 91 had a similar problem.
I changed the Headlight Control Module which worked for about a day and I also, checked the linkage and wire connections for any shorts or chaffing.
Every night before leaving work, I had to manually raise (with the headlight **** on top of the motor) the headlight that wouldn't come up. I also, changed the headlight motor bushings and plastic gears a year before.
Out of frustration, I ordered two rebuilt headlight motors from Eckler's and they've been fine for the past three years! I even reinstalled the original Headlight Control Module since the replacement I bought failed a week later.
I figured something in the motor itself (windings, brushes etc...) was causing the motor from working properly.
http://www.ecklers.com/corvette-head...1991-1996.html
I changed the Headlight Control Module which worked for about a day and I also, checked the linkage and wire connections for any shorts or chaffing.
Every night before leaving work, I had to manually raise (with the headlight **** on top of the motor) the headlight that wouldn't come up. I also, changed the headlight motor bushings and plastic gears a year before.
Out of frustration, I ordered two rebuilt headlight motors from Eckler's and they've been fine for the past three years! I even reinstalled the original Headlight Control Module since the replacement I bought failed a week later.
I figured something in the motor itself (windings, brushes etc...) was causing the motor from working properly.
http://www.ecklers.com/corvette-head...1991-1996.html
Last edited by GKK; Aug 27, 2010 at 01:19 PM.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
^^my thoughts exactly......Electrical motors do not last forever.
You can check if a motor is getting worn by the resistance......which by the way is what The Module reads for shutting off power when the bucket has reached the rubber stoppers....
You can check if a motor is getting worn by the resistance......which by the way is what The Module reads for shutting off power when the bucket has reached the rubber stoppers....
Heel & Toe
Joined: Jan 2005
Posts: 19
Likes: 0
Can anyone tell me where each of the wires on the 5wire plug of the module go? I have a significant battery drain caused by terminal B and cannot seem to eliminate it. The interesting thing is that I think terminal E does the same for the opposite side of the car but causes no drain? Ideas?
Currently I have A: power up from the switch, B and E are Constant 12volt to power each motor, C is power down from the switch and D is ground. Is this correct?
Currently I have A: power up from the switch, B and E are Constant 12volt to power each motor, C is power down from the switch and D is ground. Is this correct?