Headlight issues

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Orange

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I’ve had this problem for a few months now on my 87 gmc. It started out with the left blinker now working while the lights were on and now it evolved into this huge mess. I’m not good with electronics so I don’t even know where to start, can anyone help?
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This is low beams
 

Bextreme04

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Check the ground connectors inside the bulb holders. Mine had an issue where the turn signals wouldn’t flash when the headlights were on(they would flash once or twice and then go solid) and it turned out the ground connector on one of the side markers had broken off inside the bulb connector. I was able to shove it back in there and twist it into place to get wedged in there and had worked perfect ever since.
 

Ricko1966

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I'd start sanding all the bulb contacts and connections. Unplug the headlights sand the terminals put sockets back on.remove all the mini bulbs sand the outside of the metal base, sand the lead terminals, sand the inside of the lamp socket including the contacts. Still have a problem put a mirror where you can watch the bulbs while you wiggle the wiring harness starting at the bulbs and working back,to the harness ground undo it sand everything and put it back together.
 
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79dentside

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I had a grounding issue on my drivers side headlight, the wires wire bent too harshly so I took the strain out of them and it seemed to fix it. Occasionally I would have to re-adjust the grounds if the light went dim again.
 
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Ricko1966

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I'd start by sanding all the bulb contacts and connections. Unplug the headlights sand the terminals put sockets back on.remove all the mini bulbs sand the outside of the metal base, sand the lead terminals, sand the inside of the lamp socket including the contacts. Still have a problem put a mirror where you can watch the bulbs while you wiggle the wiring harness starting at the bulbs and working back,to the harness ground undo it sand everything and put it back together.
 

Orange

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Also a side note, the left indicator dash light comes on solid when the lights are on
 

Matt69olds

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Check each ground. If you have to occasionally wiggle the wires, you don’t have a good ground. As mentioned before, lightly sand every bulb connector, lightly sand the bulb contacts, coat the socket with dielectric grease and reinstall the bulbs.
 

Matt69olds

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Also a side note, the left indicator dash light comes on solid when the lights are on


Make sure someone hasn’t put a single filament bulb (1156 bulb) in place where a dual filament bulb (1157) should be.

Another possibility is a bad ground on the left turn signal socket, or a defective socket itself.
 

Snoots

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Grounding issue.
 

Cuba

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Also a side note, the left indicator dash light comes on solid when the lights are on

What you see on the dash and what is lit outside have nothing to do with each other.

The sockets/connectors on these lights do tend to get green crusties and pin fin fitment tension is weakened over time. With the headlights on, just reach behind and wiggle the connector. If light flickers or changes intensity, just change the socket/connector. They aren't expensive. But PLEASE, for the love of God... use marine grade heat shrink or crimp connectors. DON'T use scotch locks or cheap Harbor Freight butt connectors.

Poor ground is also a huge factor. They tend to daisy chain the ground so points can also corrode over time.
 

Dooley

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The Black wire ground problems throughout the "forward lamp harness" could be the result of a poorly done press crimp as most all those wires are crimped together in the wiring, dip soldered and then wrapped with duct tape. I have seen some crimps where a wire or 2 would be lucky to have even one strand "caught" in the crimp. Look inside the conduit.
 

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A different headlight issue.
I also had gremlins and knew about the ground problems but now I have a headlight relay kicking in and out on high beam only.
Suggestions?
 

Cuba

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A different headlight issue.
I also had gremlins and knew about the ground problems but now I have a headlight relay kicking in and out on high beam only.
Suggestions?
Check pin fitment at the relay. Or the relay itself. To activate a relay, it's minimal current... so fitment could be the only issue... or losing the control signal from the switch.
 

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