"91" Headlight Control Module.
#1
Safety Car
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"91" Headlight Control Module.
Recently the headlights on my "91" Vette have been having an intermittent problem.
The right side headlight would not rotate up but lights up. If I rotate the manual **** a little, turn the headlight switch off and back on again, both headlights work fine for several tries.
When I turn the headlights on again several hours later, sometimes the driver side headlight won't rotate up but still lights up. If I rotate the manual **** a little, turn the headlight switch off and back on again, both headlights work fine again.
When I was driving home in the afternoon, I turned on the headlights just to see if they would work and both of the headlights wouldn't rotate up.
I checked power from the two red power wires going to the Headlight Control Module and both wires have 12.5 volts. I've ruled out the fusible links, motor assembly's and relays since everything actually works but, just intermittently. Also, all connections are clean.
I took apart the Headlight Control Module and I didn't see any bad or burnt solder joints. After searching here on the forum, I've narrowed it down to the Headlight Control Module, I just wanted to check here first from others who have experienced this problem before I spend $165 for a new headlight control module.
Thanks for your help.
The right side headlight would not rotate up but lights up. If I rotate the manual **** a little, turn the headlight switch off and back on again, both headlights work fine for several tries.
When I turn the headlights on again several hours later, sometimes the driver side headlight won't rotate up but still lights up. If I rotate the manual **** a little, turn the headlight switch off and back on again, both headlights work fine again.
When I was driving home in the afternoon, I turned on the headlights just to see if they would work and both of the headlights wouldn't rotate up.
I checked power from the two red power wires going to the Headlight Control Module and both wires have 12.5 volts. I've ruled out the fusible links, motor assembly's and relays since everything actually works but, just intermittently. Also, all connections are clean.
I took apart the Headlight Control Module and I didn't see any bad or burnt solder joints. After searching here on the forum, I've narrowed it down to the Headlight Control Module, I just wanted to check here first from others who have experienced this problem before I spend $165 for a new headlight control module.
Thanks for your help.
#2
Safety Car
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After more testing, I came to the conclusion that it has to be the headlight control module. I ordered one from Mid America part# 611-627 and I'll post if it solves the problem.
#3
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Location: Fort Knox, KY
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Sounds like you nailed it, but it might not be a bad idea to replace your headlight motor bushings, too.
They grind themselve to powder, resulting in your motors spinning, slipping and failing after 10 years or so or typical use.
They grind themselve to powder, resulting in your motors spinning, slipping and failing after 10 years or so or typical use.