what did I do? no headlights

[Mr_Geenie]

2003 International Bluebird 3800.
I took my hood off to paint it, put it back on, reconnected everything except the mirror heaters I have no use for in South Texas and my headlights don't turn on. Low or High.
Usually they are always on "low-low" and I pull the headlight switch out and low beams get full voltage and get a little brighter, then the switch makes high beams come on.
All other lights work.

[TheHubbardBus]

The first place I'd look is the harness connector where the two headlights / front turns combine. On our bus it's in the engine compartment, along the driver-side frame rail, near the lower corner of the radiator. Yours may be different, but to remove the hood you have to disconnect the headlight harness somewhere. Wherever that somewhere is is what I'd check.

[Mr_Geenie]

I started there, traced it all the way back to the switch and the dimmer switch. All the wires were good, fuses got checked next. All the fuses were good. So I rechecked all the wires. Spent 4 hours looking for a disconnected wiring harness.
Took an multimeter to my headlights....
Open line. Both bulbs went bad corroded at the terminals. The high beam on one of them will work with a jumper wire, the other one is completely shot. Wouldn't surprise me if that was the original headlamp.
I feel like a dumbass for not checking the bulbs first. But what are the odds that both headlights high and low would go bad at the same time?

They LOOKED in usable shape. They worked when I took the hood off. NOPE. The bus demands another financial sacrifice.

[TheHubbardBus]

Originally Posted by Mr_Geenie

I feel like a dumbass for not checking the bulbs first. But what are the odds that both headlights high and low would go bad at the same time?

Not a dumbass. That's a freak coincidence. Diagnosing problems should start from most likely to least, which is what you did. Sometimes fate just throws you a curveball.

[HamSkoolie]

If they worked before you went in there (worked on it) then the problem was likely caused by your actions disrupting what had been working. Not uncommon for that to happen
Corrosion that is still making contact until disturbed is a common issue in aged electrical circuits.