headlight / electrical guru needed
Thread Starter
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Joined: Mar 2023
Posts: 81
Likes: 36
From: Louisiana
headlight / electrical guru needed
Since I bought this car almost a year ago, the headlights have been intermittent at going down.
Up always worked perfectly. Tried the resolder fix on the control module. only worked for about
a week, then back to staying up. A few months ago, I ordered Sleepy eye kit for headlights, and
decided to change the headlight control module (HCM) while I was installing headlights.
When the headlights (finally) came in, I installed kit with original HCM first, to insure no issues.
Headlights working correctly. Today, I installed the new HCM (129.00 brand new from EBay)
So, it works. lights on, headlights up in headlight position, off and retracted in OFF position,
but when turned to parking light position, headlights retract (parking lights stay on, and halos
in new sleepy eye kit are on as designed) but headlights do not stay up.
Whatever is supposed to give it a signal to close when parking lights go off, is instead signaling
them to close when headlights power off. I doubt sending the HCM back will make a difference,
that's probably the way that they are made. So is there a wire that I can switch to make this
work as it should?
Up always worked perfectly. Tried the resolder fix on the control module. only worked for about
a week, then back to staying up. A few months ago, I ordered Sleepy eye kit for headlights, and
decided to change the headlight control module (HCM) while I was installing headlights.
When the headlights (finally) came in, I installed kit with original HCM first, to insure no issues.
Headlights working correctly. Today, I installed the new HCM (129.00 brand new from EBay)
So, it works. lights on, headlights up in headlight position, off and retracted in OFF position,
but when turned to parking light position, headlights retract (parking lights stay on, and halos
in new sleepy eye kit are on as designed) but headlights do not stay up.
Whatever is supposed to give it a signal to close when parking lights go off, is instead signaling
them to close when headlights power off. I doubt sending the HCM back will make a difference,
that's probably the way that they are made. So is there a wire that I can switch to make this
work as it should?
Last edited by tookielee; Feb 24, 2024 at 08:07 PM.
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Pro
Joined: Aug 2010
Posts: 622
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From: Montgomery Texas
Just to clarify, you are saying that the lights function normally, but with one exception:
When the light switch is switched from "headlights" mode to "parking lights" mode the headlights switch off and the headlight doors close, instead of the headlight doors remaining open as would normally be expected. Is this correct?
Q: How are the halos powered? Are you tapping into the front parking light circuit? If so, how and where? Did your halos come with instructions and/or a wiring diagram that you can post?
BTW - It seems to me that I have read a few complaints that some brands of LED switchback lights can cause the headlight doors to do strange things. I would disconnect the halos to see if this makes any difference. If you have LED switchbacks, I would go and get some 1157 bulbs for testing and stick them in the front turn signal housings to see if this makes any difference. If it does, get some quality LED switchbacks from George, AKA - TheRadioFlyer.
When the light switch is switched from "headlights" mode to "parking lights" mode the headlights switch off and the headlight doors close, instead of the headlight doors remaining open as would normally be expected. Is this correct?
Q: How are the halos powered? Are you tapping into the front parking light circuit? If so, how and where? Did your halos come with instructions and/or a wiring diagram that you can post?
BTW - It seems to me that I have read a few complaints that some brands of LED switchback lights can cause the headlight doors to do strange things. I would disconnect the halos to see if this makes any difference. If you have LED switchbacks, I would go and get some 1157 bulbs for testing and stick them in the front turn signal housings to see if this makes any difference. If it does, get some quality LED switchbacks from George, AKA - TheRadioFlyer.
Last edited by Tron Z; Feb 29, 2024 at 06:50 PM.
Former Vendor
Joined: May 2022
Posts: 128
Likes: 17
From: Texas
Multifunction Switch commands the doors to close when you turn the headlights off; I’d guess you have a bad switch. Can be caused by a bad headlight door control module pulling too much current. To confirm, you can try slowly turning the barrel switch from on to park until the moment the headlights go out (before the detent.). If the doors stay up, it’s your switch. If they both act at the same time, it’s likely the module- small chance it’s still the switch. Hope that helps!
I also sell and repair these switches on eBay!
I also sell and repair these switches on eBay!
Burning Brakes
Joined: Nov 2021
Posts: 777
Likes: 382
From: Old Dominion - VA
Multifunction Switch commands the doors to close when you turn the headlights off; I’d guess you have a bad switch. Can be caused by a bad headlight door control module pulling too much current. To confirm, you can try slowly turning the barrel switch from on to park until the moment the headlights go out (before the detent.). If the doors stay up, it’s your switch. If they both act at the same time, it’s likely the module- small chance it’s still the switch. Hope that helps!
I also sell and repair these switches on eBay!
I also sell and repair these switches on eBay!
Thread Starter
Advanced
Joined: Mar 2023
Posts: 81
Likes: 36
From: Louisiana
Bought a reproduction headlight control module from E-bay, kind that says "John 4:16" or some such on it.
Original HCM was faulty, doors opened every time, but occasionally would not close. But would close every time
f I wiggled the plug or wire at the 5 pin connector, no issue with multi function switch. Tried to resolder the original switch,
did not help. But I only touched up the solder at the plugs, not the smaller connections on the circuit board. I'm pretty
sure it's one of those, but I didn't feel like messing with it anymore, and the repro unit was cheap. It works well, but
it would be nice to be able to leave doors up with headlights off, either to work on things, or to see my pretty new halos.
And halos are wired into park light circuit, everything worked correctly prior to new HCM, except doors would not
always close.
It would be great if there was an external wire I could reconfigure, but I fear it is the way the new HCM is made.
Original HCM was faulty, doors opened every time, but occasionally would not close. But would close every time
f I wiggled the plug or wire at the 5 pin connector, no issue with multi function switch. Tried to resolder the original switch,
did not help. But I only touched up the solder at the plugs, not the smaller connections on the circuit board. I'm pretty
sure it's one of those, but I didn't feel like messing with it anymore, and the repro unit was cheap. It works well, but
it would be nice to be able to leave doors up with headlights off, either to work on things, or to see my pretty new halos.
And halos are wired into park light circuit, everything worked correctly prior to new HCM, except doors would not
always close.
It would be great if there was an external wire I could reconfigure, but I fear it is the way the new HCM is made.
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Thread Starter
Advanced
Joined: Mar 2023
Posts: 81
Likes: 36
From: Louisiana
Actually, it's the HCM that commands doors to close. I'm guessing it should send a signal to open when headlights come on, and
to close when headlights go off, and no signal when switched from headlights to parking lights.
Former Vendor
Joined: May 2022
Posts: 128
Likes: 17
From: Texas
I mention my method because the headlight door close supply to the MFS is the same as the parking light supply to the MFS, which supplies power directly to the parking lights. If your parking lights or HCM are causing heat, it can melt the MFS cam, causing the OFF contact to close, causing the doors to close.
Last edited by Tony Corvette; Mar 2, 2024 at 10:24 AM.
Thread Starter
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Joined: Mar 2023
Posts: 81
Likes: 36
From: Louisiana
Yeah, but this is a brand new reproduction unit, worked this way since I put it in a
couple of weeks ago. Not the switch, I can plug in the original HCM and it works correctly.
I think I'll go over the solder contacts on original again, if I get it right, I'll keep
the new one for an emergency
couple of weeks ago. Not the switch, I can plug in the original HCM and it works correctly.
I think I'll go over the solder contacts on original again, if I get it right, I'll keep
the new one for an emergency