headlight problem

[scotsdale83]

I finally got my 83 2wd back on the road after a complete resto mod. Took it for a ride tonight. I found the headlights to be very dim. When I got back I checked the voltage at the back of the headlight plugs got around 10.2 V and battery voltage was 12.7 with truck off. I know about the relay mod. But was wondering if something else is wrong. My 87 only has single headlights and is twice as bright as the 4 on the 83. 87 dosent have the relay mod yet ethier.

Thanks for your help

Also completly new painless harness. So no bad wires. I was thinking ground problem or lack there of

 

[StevoandaRedK5]

Also completly new painless harness. So no bad wires. I was thinking ground problem or lack there of

Most likely your problem is a bad ground (or grounds). I would check those and if that isn't it, check both the power to and the resistance on your headlight switch.

 

[scotsdale83]

Resistance on headlight switch thats a very good possibility. I have grounds from the headlights to the radiator support, rad support to frame, frame to engine, engine to cab, battery to engine. Maybe ones loose? Will check tommorow night.

 

[StevoandaRedK5]

I did a complete rewire on my K5 not too long ago, i had to pull quite a few grounds and wire brush beneath them to make good contact. 90-95% time that's the culprit on these vehicles.

 

[sweetk30]

big help from the factory lots of people leave out is the star washers. thay bit in both the body and the terminal end to get better contact.

 

[scotsdale83]

You will never see battery voltage at the headlights with out the relay mod, correct? What volatge should I see at the headlights with stock wiring? 2.5 volts seems like a wicked loss

 

[StevoandaRedK5]

It is true that you won't see full voltage at the headlight, but it shouldn't drop that much. I never tested mine before I did the relay mod, so I don't know what a normal value would be.