‘85 Headlight Motor Won’t Open, But Will Close
Thread Starter
5th Gear
Joined: May 2022
Posts: 5
Likes: 0
From: CT
‘85 Headlight Motor Won’t Open, But Will Close
Hi All,
Long time reader, first time posting.
My drivers side headlight motor stopped flipping up, yet when I use the manual **** then plug the motor back in it closes just fine. I know there’s many threads on headlight motor issues, but none that I have seen with the same exact problem as me so they’ve been little to no help, and I’ve hit a wall trying to figure it out.
I ran some tests:
Open:
Grn 12V
White 0
Grey 0
Closed
Grn 0
White 0
Grey 12V
Keep in mind all of these readings are while the motor is disconnected, testing through the pins.
From what I gather, this is all correct and working how it should be. That lead me to believe that it’s the motor. I replaced the motor… same problem. Goes down, can’t go up. I called a corvette specialist and he said it was the crappy reman I bought that came with another bad limit switch, and at first I agreed with him.
I figured I’d do some more tests for the hell of it though, and found something very strange to me. I connected the new reman to the passenger side clip and it worked just fine, spun both ways.
Also, as I said earlier, when the motor was disconnected the White wire showed 0V. I reconnected the motor and the white wire now has voltage. 12V.
What can cause this and how do I fix it?
-Mike
Long time reader, first time posting.
My drivers side headlight motor stopped flipping up, yet when I use the manual **** then plug the motor back in it closes just fine. I know there’s many threads on headlight motor issues, but none that I have seen with the same exact problem as me so they’ve been little to no help, and I’ve hit a wall trying to figure it out.
I ran some tests:
Open:
Grn 12V
White 0
Grey 0
Closed
Grn 0
White 0
Grey 12V
Keep in mind all of these readings are while the motor is disconnected, testing through the pins.
From what I gather, this is all correct and working how it should be. That lead me to believe that it’s the motor. I replaced the motor… same problem. Goes down, can’t go up. I called a corvette specialist and he said it was the crappy reman I bought that came with another bad limit switch, and at first I agreed with him.
I figured I’d do some more tests for the hell of it though, and found something very strange to me. I connected the new reman to the passenger side clip and it worked just fine, spun both ways.
Also, as I said earlier, when the motor was disconnected the White wire showed 0V. I reconnected the motor and the white wire now has voltage. 12V.
What can cause this and how do I fix it?
-Mike
Last edited by MikeArena; May 10, 2022 at 10:42 AM. Reason: Info Missing
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
Hi All,
Long time reader, first time posting.
My drivers side headlight motor stopped flipping up, yet when I use the manual **** then plug the motor back in it closes just fine. I know there’s many threads on headlight motor issues, but none that I have seen with the same exact problem as me so they’ve been little to no help, and I’ve hit a wall trying to figure it out.
I ran some tests:
Open:
Grn 12V
White 0
Grey 0
Closed
Grn 0
White 0
Grey 12V
Keep in mind all of these readings are while the motor is disconnected, testing through the pins.
From what I gather, this is all correct and working how it should be. That lead me to believe that it’s the motor. I replaced the motor… same problem. Goes down, can’t go up. I called a corvette specialist and he said it was the crappy reman I bought that came with another bad limit switch, and at first I agreed with him.
I figured I’d do some more tests for the hell of it though, and found something very strange to me. I connected the new reman to the passenger side clip and it worked just fine, spun both ways.
Also, as I said earlier, when the motor was disconnected the White wire showed 0V. I reconnected the motor and the white wire now has voltage. 12V.
What can cause this and how do I fix it?
-Mike
Long time reader, first time posting.
My drivers side headlight motor stopped flipping up, yet when I use the manual **** then plug the motor back in it closes just fine. I know there’s many threads on headlight motor issues, but none that I have seen with the same exact problem as me so they’ve been little to no help, and I’ve hit a wall trying to figure it out.
I ran some tests:
Open:
Grn 12V
White 0
Grey 0
Closed
Grn 0
White 0
Grey 12V
Keep in mind all of these readings are while the motor is disconnected, testing through the pins.
From what I gather, this is all correct and working how it should be. That lead me to believe that it’s the motor. I replaced the motor… same problem. Goes down, can’t go up. I called a corvette specialist and he said it was the crappy reman I bought that came with another bad limit switch, and at first I agreed with him.
I figured I’d do some more tests for the hell of it though, and found something very strange to me. I connected the new reman to the passenger side clip and it worked just fine, spun both ways.
Also, as I said earlier, when the motor was disconnected the White wire showed 0V. I reconnected the motor and the white wire now has voltage. 12V.
What can cause this and how do I fix it?
-Mike
Thread Starter
5th Gear
Joined: May 2022
Posts: 5
Likes: 0
From: CT
With the headlight switch ON, read voltage between Green and White with the motor unplugged. It should be 12 volts. (Green positive, White negative). If the Green wire has 12 volts to chassis ground (but not to the white wire) the relay for the LH door is faulty in that the white wire is not being switch to ground.
A quick test would be to swap the two 5-wire relays. If the driver door now works, and the passenger does not, you have the answer: Faulty relay that is now on the striped wires.
A quick test would be to swap the two 5-wire relays. If the driver door now works, and the passenger does not, you have the answer: Faulty relay that is now on the striped wires.
Thanks for the quick test tip. I definitely would’ve done that if I hadn’t already bought the relay, and will be keeping it in mind for future reference.
