No lights-Help please

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jka251

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Got this truck a few months ago. No head, tail or gauge lights. I’ll start with my headlights/ tail lights. It doesn’t seem I’m getting any power to the light switch. The red wire should be hot, correct? I’ve tried to trace it but the engine was swapped and I’m not 100% sure where it goes. There’s new wires ran for the ignition and other stuff that I’m not sure of yet. There are a couple other red wires under the hood that connect to a red wire coming out of the firewall. Those wires are hot. But they go to some type of junction block that just seem to go to the A/C?? Any help as to what I need to look for is appreciated.
 

HotRodPC

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Test the hot wire coming into the headlight switch. If it's Hot, then you're likely got a bad headlight switch, with all that not working. If it was just headlights, I'd say check the dimmer switch, if it were just the dome, tail and dash lights I'd say it's the fuse to the circuit, but both headlights and all those others not working, I'd first suspect a bad switch, IF I HAVE KNOWN POWER to the switch.
 

jka251

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I tested the red wire on the switch. It is not hot. Not sure where to go next.
 

Snoots

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Trace that wire to its source.
 

HotRodPC

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IIRC, it goes right back to the fuse block.
 

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You can also put power to that wire and check for operational lights.
 

HotRodPC

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Yep, run a KNOWN hot wire direct to it and see if it lights up. Then you know the switch is good.

And I'm sure you did right? I ALWAYS ALWAYS ALWAYS his my test light to something hot using the same exact ground I'm testing with to make sure my bulb is good and my ground is good on the test light.
 

jka251

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Just ran a piece of wire from the red wire on the light switch to a hot wire under the hood. When I touched my test wire to the known hot wire, the engine started turning over. So, I ran my test wire from the red wire on the light switch straight to the battery terminal. The engine started turning over again. Like I said earlier, there was an engine swap and some shade tree wiring done. Thank y’all for the help so far. Keep it coming. I’m still in the dark.
 

jka251

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Also, I just ran a test wire from the battery to a headlight and it lit up. At least the lights work. Just need to get power to them.
 

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