head hights wont come on when it is cold
Check all of the electrical grounds.
My '74 Volvo had the same problem–plus MANY other electrical problems-- and they were eventually traced to ground problems. If you live in The UK, these would be referred to as “earth” problems.
A faulty headlight switch can cause that.
I owned a 94 Silverado myself. Great truck and I miss it. I would look at the headlight switch itself first. I work at a scrapyard and could get one for free to swap out, though.
Tester beat me to it and he’s probably never owned a 94 Chebbie. That rascal
Two people’s separated by a common language.
Do you have sealed beam headlights? If so the electrical circuit is pretty easy. Headlight switch assembly to headlight dimmer switch to right and left headlight, to chassis ground. The diagnostic method is use the wiring diagram to trace the circuit from the start to the end until you find a problem where the power isn’t getting through. If I had that problem I’d start by testing the resistance of the bulb filaments. Is the high beam indicator on the dash working? If not, that would be a clue.
Considering the age of the truck and the number of switch cycles it has likely gone through I tend to think the headlight switch is failing. Another possibility is poor contacts inside a headlamp relay.
On my truck, you had to jiggle the switch or the dimmer (can’t recall for sure), then the lights would come on. I replaced the offending component with a scrapyard piece. Might be a good test to see if one of those is at fault. Jiggle the switch and dimmer when the lights don’t work.