headlite motor won't stop
Thread Starter
Cruising
Joined: Jul 2006
Posts: 11
Likes: 0
From: Omaha Nebraska
headlite motor won't stop
Hey guys. I just finished replacing the bushings in the right side motor and getting everything back together. I ran it up and down a couple of times with the manual control to make sure there was no binding and everything worked smooth. THen I turned the lites on with the switch and both went up perfectly. Then the problem surfaced. When I turned the lites off, both went down okay, but the one I worked on, the motor doesn't stop when it should. It runs for a few seconds, maybe 10 or so, and the manual *** hops up and down about three times. I thought maybe it was not in the right cycle, so I manually lowered the repaired lite about half way and tried with the switch again. Went up good and came down good but the motor still continued to run.
Any ideas on a cure?
Any ideas on a cure?
Melting Slicks
Joined: Jul 2004
Posts: 3,235
Likes: 1
From: Sterling Va
The big silver shaft that runs through the gear is stripped so it is not biting on the gear. I had this problem once and drilled a hole though it a put a screw through it.
Take it apart hold the gear and put a small screw driver though the hole at the end of the shaft and try to turn it. If it does then I confirms my diagnosis.
Take it apart hold the gear and put a small screw driver though the hole at the end of the shaft and try to turn it. If it does then I confirms my diagnosis.
Thread Starter
Cruising
Joined: Jul 2006
Posts: 11
Likes: 0
From: Omaha Nebraska
headlite motor won't stop
I did not replace the gear. It had no missing teeth when Iput it back together. The shaft that goes through the gear has no teeth. Do these motors have some kind of a switch that when they meet resistance that they should stop?
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Originally Posted by 90convertible for me
I did not replace the gear. It had no missing teeth when Iput it back together. The shaft that goes through the gear has no teeth. Do these motors have some kind of a switch that when they meet resistance that they should stop?
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Yes they do. When the headlight rotates and runs into the bumpers, its supposed to shut off. There is a switch for this, although i'm not sure where it is.
There is no switch or to be exact, limit switches that control the movement of the mechanism from end to end.
Here's a description of how it works instead.
The headlight controller has current sense circuitry that measures the current rise when the mechanism reaches the end of it's travel either fully extended or fully extracted and the drive motor approaches it's stall
or full torque current draw.
This curcuitry controls the motor drive circuit in the headlight control module. It cuts the motor drive off so that the motors don't keep running when the headlight mechanism reaches either stop.
The circuitry is designed to make sure the headlight motors don't continue to receive voltage from the motor drive circuitry after they have reached a stall or near stall condition.
In normal operation, this takes the place of less reliable limit switches and protects the motors.
In abnormal circumstances in case of a mechanism jam, etc.,
the circuitry keeps the motors from overheating and possibly starting a FIRE under the hood.
This is the reason for the sticker on the back of the module warning 'folks' not to tamper with the circuitry inside.
I have NO doubt that sticker wasn't aimed at me, LOL.
Last edited by VetNutJim; Sep 18, 2006 at 12:09 AM.
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Originally Posted by VetNutJim
His 90 has the same headlight control system my 91 has.
There is no switch or to be exact, limit switches that control the movement of the mechanism from end to end.
Here's a description of how it works instead.
The headlight controller has current sense circuitry that measures the current rise when the mechanism reaches the end of it's travel either fullly extended or fully extracted.
This curcuitry controls the motor drive circuit in the headlight control module. It cuts the motor drive off so that the motors don't keep running when the headlight mechanism reaches either stop.
The circuitry is designed to make sure the headlight motors don't continue to receive voltage from the motor drive circuitry after they have reached a stall or near stall condition.
In normal operation, this takes the place of less reliable limit switches and protects the motors.
In abnormal circumstances in case of a mechanism jam, etc.,
the circuitry keeps the motors from overheating and possibly starting a FIRE under the hood.
This is the reason for the sticker on the back of the module warning 'folks' not to tamper with the circuitry inside.
I have NO doubt that sticker wasn't aimed at me, LOL.
There is no switch or to be exact, limit switches that control the movement of the mechanism from end to end.
Here's a description of how it works instead.
The headlight controller has current sense circuitry that measures the current rise when the mechanism reaches the end of it's travel either fullly extended or fully extracted.
This curcuitry controls the motor drive circuit in the headlight control module. It cuts the motor drive off so that the motors don't keep running when the headlight mechanism reaches either stop.
The circuitry is designed to make sure the headlight motors don't continue to receive voltage from the motor drive circuitry after they have reached a stall or near stall condition.
In normal operation, this takes the place of less reliable limit switches and protects the motors.
In abnormal circumstances in case of a mechanism jam, etc.,
the circuitry keeps the motors from overheating and possibly starting a FIRE under the hood.
This is the reason for the sticker on the back of the module warning 'folks' not to tamper with the circuitry inside.
I have NO doubt that sticker wasn't aimed at me, LOL.
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Joined: Oct 2000
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From: Fort Knox, KY
Cruise-In IV Veteran
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Cruise-In VIII Veteran
Make sure the gear housing is bolted together properly. If there are any gaps between the housing and the enclosure, it can cause this problem.
Thread Starter
Cruising
Joined: Jul 2006
Posts: 11
Likes: 0
From: Omaha Nebraska
Headlite motor won't stop
One more question. Is the piece of metal that goes between the motor and the bracket supposed to be able to rotate or not? If it rotates, I can't figure out how it could act as a stop. I might also suggest to others that when they change the bushings to put a little grease on them to lessen the friction and make them last longer. None of the posts I have seen suggest this.
Instructor
Joined: Mar 2005
Posts: 174
Likes: 3
From: Yorba Linda CA
Don't mean to rob the thread but I thought I'd pass this along. You might want to get plastic headlamps. 2 plastic lamps weigh less than 1 glass unit. I found this out by accident. I have a 95 and when I bought it it had glass units and when one burned out I researched the issue and found the original that came from the factory were plastic so I got those. Boy, what a difference! They open a lot faster!...and are obviously less strain on the headlight running gear. They are available from your local NAPA store, Part # HP6054 Halogen and replace 6052,6054. I don't detect any difference in brightness between them and glass though being plastic I figure they may dull a bit over time. I'm not sure whether 95s and 90s have the same type of headlamp so you might want to check this out.
Thread Starter
Cruising
Joined: Jul 2006
Posts: 11
Likes: 0
From: Omaha Nebraska
Headlite motor thought Ihad it fixed.
Well, it faked me out. It worked a few times but no more. I discovered that the floppy thing(the stop) gets bound up and can't rotate. If i pry with screwdriver between the floppy thing and the brass block that the motor shaft goes through, I can loosen it up and it will work once. I am considering bending the bracket that the brass block is attached to slightly towards the lite bulb, away from the motor to see if that would keep the floppy thing loose enough to pivot. But I don't want to try that until someone else thinks it may work. Incidentally, I have not put a cotter pin through the brass piece and the motor shaft as it would be pulled even further and be tight all the time. Any opinions?
Thanks.
Thanks.
6th Gear
Joined: Sep 2006
Posts: 6
Likes: 0
I just purchased my 89 last week and it has the same problem. Oddly enough, the previous owner just had both motors replaced last year with new ones to the tune of $325 ea. I don't think that it should be doing that this early. It not only does it when turning the headlights off, but if I only turn the parking lights on it will run the motors for a few seconds when I shut them off. Any ideas?
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
Originally Posted by 4Ever21
Yes they do. When the headlight rotates and runs into the bumpers, its supposed to shut off. There is a switch for this, although i'm not sure where it is.