Two switches, inside the motor assy. Contact breakers that open when the armature 'shifts' against springs when the headlight hits the travel stops. The adjustment is a bit finicky...
Headlight motor question.
Thread Starter
Racer
Joined: May 2006
Posts: 293
Likes: 29
From: Columbus Ohio
Headlight motor question.
Just curious.....
Can someone tell me what stops the headlight motors once the lights reach the full open/closed position? I dont see any limit switches on it. Is there an electrical breaker that detects the increased load when it hits the stops and shuts it off?
Can someone tell me what stops the headlight motors once the lights reach the full open/closed position? I dont see any limit switches on it. Is there an electrical breaker that detects the increased load when it hits the stops and shuts it off?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Originally Posted by CCRed
Just curious.....
Can someone tell me what stops the headlight motors once the lights reach the full open/closed position? I dont see any limit switches on it. Is there an electrical breaker that detects the increased load when it hits the stops and shuts it off?
Can someone tell me what stops the headlight motors once the lights reach the full open/closed position? I dont see any limit switches on it. Is there an electrical breaker that detects the increased load when it hits the stops and shuts it off?
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Originally Posted by CCRed
Is there an electrical breaker that detects the increased load when it hits the stops and shuts it off?
If this is for your 88, the headlight control module which is mounted on the front of the driver side plastic wheel well housing, monitors the currrent draw from each motor and will shut off the power to the motor if the current draw exceeds a certain value.
The 12 volts that drives the motors is supplied by 2 fusible links.
The service manual only shows a block diagram of the control module. It appears there is no circuit breaker that protects the motor circuit other than the fusible links.
Thread Starter
Racer
Joined: May 2006
Posts: 293
Likes: 29
From: Columbus Ohio
OK two different answers.... must be different from year to year.
Anyone know specifically about an '88?
The reason I ask is because so many say their bushings "turned to dust". Nylon is an ecological nightmare because it does not just "turn to dust" or disintegrate and its all still in there. I suspect whatever stops the motor gets out of wack and slowly grinds the bushings up.
Anyone know specifically about an '88?
The reason I ask is because so many say their bushings "turned to dust". Nylon is an ecological nightmare because it does not just "turn to dust" or disintegrate and its all still in there. I suspect whatever stops the motor gets out of wack and slowly grinds the bushings up.
Thread Starter
Racer
Joined: May 2006
Posts: 293
Likes: 29
From: Columbus Ohio
Originally Posted by Hooked on Vettes
You should always post what year vette your question concerns.
If this is for your 88, the headlight control module which is mounted on the front of the driver side plastic wheel well housing, monitors the currrent draw from each motor and will shut off the power to the motor if the current draw exceeds a certain value.
The 12 volts that drives the motors is supplied by 2 fusible links.
The service manual only shows a block diagram of the control module. It appears there is no circuit breaker that protects the motor circuit other than the fusible links.
If this is for your 88, the headlight control module which is mounted on the front of the driver side plastic wheel well housing, monitors the currrent draw from each motor and will shut off the power to the motor if the current draw exceeds a certain value.
The 12 volts that drives the motors is supplied by 2 fusible links.
The service manual only shows a block diagram of the control module. It appears there is no circuit breaker that protects the motor circuit other than the fusible links.
We must have posted close to the same time. Do you know if there is anyway to set/change the value of the current draw limit?
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
84-87 Headlight motors use mechanical limit switches and 3 relays. (Motors have 3 wires). No bushings inside the motor just gears which do go bad and some times the limit switches need tweaking.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
Last edited by Hooked on Vettes; Jul 31, 2006 at 05:22 PM.
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Thread Starter
Racer
Joined: May 2006
Posts: 293
Likes: 29
From: Columbus Ohio
Originally Posted by Hooked on Vettes
84-87 Headlight motors use mechanical limit switches and 3 relays. (Motors have 3 wires). No bushings inside the motor just gears which do go bad and some times the limit switches need tweaking.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
3rd Gear
Joined: Aug 2006
Posts: 3
Likes: 0
'85 LH headlamp motor "running on"
During some routine work on my friend's '85, I turned the headlights ON. When I turned them off, the LH motor sounded like it was still trying to turn, creating a very disturbing grinding noise. If I pull the headlamp **** OUT just a hair (just before the marker lights come on), I can make the buzzing stop. However, just pushing the switch in, (headlamps OFF) will bring the noise back. This just started happening out of the blue. I must note here that just minutes before, I had the I/C bezel (includes headlight ****) out. Can this be a switch malfunction? It almost seems too coincidental that there were no problems, I pull the headlamps ON to remove the ****, and now the LH motor buzzes. Any suggestions are appreciated. Thanks, Hays
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
Originally Posted by Hooked on Vettes
84-87 Headlight motors use mechanical limit switches and 3 relays. (Motors have 3 wires). No bushings inside the motor just gears which do go bad and some times the limit switches need tweaking.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
88-96 Headlight motors were controlled by a solid state control module. (Motors have two wires). They came from the factory with a Gel type material that acted like a clutch. Over time the Gel turns into a powder and the motor drive gears begin to slip.
The fix is to clean out the powder/Gel and install three Delrin bushings to replace the Gel. The bushings are available from Ecklers, Mid America, Corvette Central for around $5.00 for 3 bushings that will fix 1 motor. Some people have purchased some bushings from Home Depot and Lowes with mixed results.
If you manually rotate the **** on top of the headlight motor, (takes a lot of turning) the headlight bucket should open or close smoothly with no slippage.
In the majority of cases installing the bushings will cure the problem with the 88-96 headlight motors.
Very rarely will you find bad gear teeth.
There is no reason to mess with the current draw specs. of the motors.
On the tool bar on top, click on Other then C4 Tech tips and you should find a write up on how to install the bushings.
Would you happen to have a diagram of 84-87 ? Mine have been stuck in the up position since I bought the car. I can't even find electrical connectors TO the motors. At first I thought they were vacuum operated since they have some weird barb connectors on them.
-- Joe
- 1986 Original Owner -
Joined: Apr 1999
Posts: 3,193
Likes: 139
From: North Yorkshire, England
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Originally Posted by anesthes
Would you happen to have a diagram of 84-87 ?
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I dont seem to have any of the relays, and the headlight motors have had the wires removed from them. (took them apart yesterday). I have 2 3-wire connectors, one appears to be for the headlamps, and the other appears to be for the motor maybe?
I think i'll just upgrade to later style motors, since mine seem to be junk.
Thanks for the help!
-- Joe
I think i'll just upgrade to later style motors, since mine seem to be junk.
Thanks for the help!
-- Joe
3rd Gear
Joined: Aug 2006
Posts: 3
Likes: 0
Originally Posted by HAYS
During some routine work on my friend's '85, I turned the headlights ON. When I turned them off, the LH motor sounded like it was still trying to turn, creating a very disturbing grinding noise. If I pull the headlamp **** OUT just a hair (just before the marker lights come on), I can make the buzzing stop. However, just pushing the switch in, (headlamps OFF) will bring the noise back. This just started happening out of the blue. I must note here that just minutes before, I had the I/C bezel (includes headlight ****) out. Can this be a switch malfunction? It almost seems too coincidental that there were no problems, I pull the headlamps ON to remove the ****, and now the LH motor buzzes. Any suggestions are appreciated. Thanks, Hays
