73-87 Chevy _ GMC Trucks => Electrical => Topic started by: Jak220 on November 12, 2021, 12:31:23 PM

Title: Headlight Issue
Post by: Jak220 on November 12, 2021, 12:31:23 PM
Having a weird issue with the headlights on my '84 K10, when I turn the normal headlights on, both top headlights work great. Weird thing is, when I turn the highbeams on and all 4 are supposed to be on, the drivers side top bulb turns off, the other 3 remain lit. Then when I turn high beams off and go back into normal headlight mode, it comes right back on. I've tried different bulbs all with the same result. Haven't been able to locate any damage to the wiring. If it's the connector, I have a new socket and could try cutting off the old one and splicing on the new one in case maybe it's just a bad connection, but I wanted to see if anyone had any other troubleshooting ideas/had dealt with a similar issue first.

Title: Re: Headlight Issue
Post by: bd on November 12, 2021, 01:42:38 PM
Unplug the driver's side headlamp connector and saturate the terminals with WD40.  Then plug/unplug the connector onto/from the left upper headlamp repeatedly to burnish the connections and retry the high and low beams to see what happens.  If no improvement, check the headlamp ground connection to the radiator support and check for power at the back of the headlamp using a test light.