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I bought the under dash courtesy light kit from LMC for my 1978 F-250 Supercab. I don't seem to have the factory harness with the plugs like I see in some of the wiring diagrams. I would like to wire these into the existing dome light circuit so they turn on when the dome light turns on using the headlight switch as well as the door jam switches. Has anyone done this? I'd rather not add the additional door jam switches that come with the lights. If I understand correctly the green/yellow wire is always hot and the blue/black wire supplies power to the light after the switch. I should be able to tap into the switch wire (blue/black) for power and then ground the black wire? Looking for some insight before I start splicing. Thanks!
I believe you are correct, but to make sure I would go to harbor freight and buy a testlight. Clip the one lead of the testlight to a good ground, and then poke the blue/black and verify correct operation.
Thanks for the help identifying the wires. I hooked into the single blue/black wire coming out of the harness after the jam switches. Grounded the black wire from lights and now have nice lighting on the floor pans.