Flickering headlights issue

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codfish

Drive a hybrid. I NEED your gas!!
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Newfoundland
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gary
Truck Year
84
Truck Model
K10
Engine Size
350
84 K10
Dimmer switch on column

I haven't driven the truck much at night yet, but it's soon to become my daily driver, so that will change.

The 3 or 4 times I have driven it after dark, I've had a headlight issue. As far as I can remember, low beam is fine if I don't use high beam.. 90% certain.

High beams turn on, no issues. However after a few minutes, all 4 headlights (high beam and low beam) start blinking/flickering. Not a fast flicker, more like someone flashing their lights at you. And the dash lights and presumably the taillights are NOT affected by this. The last time it happened, I turned off the high beams and the low beams stayed on.

I have a new headlight switch installed already, to fix a dash light dimming issue. And I have 4 new headlights installed, as the old ones were fogged up. They are just stock type replacement bulbs, nothing fancy. I haven't driven the truck in the dark BEFORE I installed the new switch or lights, so I can't do a before and after comparison.

IF the new bulbs are drawing more amps than the old ones, is there something in the headlight electrical system that could be overheating and causing this to happen? Grounds all seem tight and clean.

I am planning to do the relay upgrade soon for the headlights. Just wondering if anyone has experienced this before and found a solution.

thanks as usual
codfish
 

Snoots

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Jimmy Sierra
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I do not have the relay upgrade but mine did this recently and I found that the fuse (under the dash) connections had corrosion on them. Cleaned that off and all is well.
 

Grit dog

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I am planning to do the relay upgrade soon for the headlights. Just wondering if anyone has experienced this before and found a solution.
I did just do the relay upgrade. With a cheapo Amazon one. It has issues. Got some voltage bleeding over to the high beams when the low beams are on. Haven't pinpointed it yet but suspect the ultra super cheap relays are the issue, considering the whole kit cost about the same a 1 quality relay.
And the plug for the signal power from an existing headlight plug was pinned wrong. 0 for 3 on getting the wires in the right spot.

Headlights aren't any brighter. Not sure if I thought they would be, as the main purpose is to keep the load from running through the old wiring and headlight switch.
 

fast 99

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Headlamps usually do not have a buss fuse they use circuit breakers. Reasoning is the headlamps won't completely leave the vehicle in the dark. Dirty connection and high amp bulbs somethimes will overload the circuit. If nothing is found in the circuit change the bulbs back to stock. Then proceed with a conversion if you want.

LED bulbs consume much less amperage than stock halogen and provide better lighting, no relay should be necessary.
 

Rickf

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I had finicky headlight issues on my old '84 C10. Turned out to be a bad connection and/or the fusible link off the starter solenoid.
 

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