no headlights

[Thunder]

I have a 1990 Jimmy that was originally tbi. The engine was blown and mostly missing when I got it. The wiring had been cut up some, seemed like just sensor connections. I installed a carbed engine and the front clip from an '82. Without cutting into any wiring yet to go from single head lights to duals I started checking lights.I have turn signals and brake lights but no marker or head lights. Is there something in the tbi wiring harness that goes to the lights? I'm thinking not but? I have changed out the headlight switch with one I know works and still nothing. What am I missing? Any help would be great.

 

[theblindchicken]

Have you checked to see if you have +12v going into the switch?

If no voltage, check the fuse box.

 

[chengny]

There should be nothing in a TBI engine wiring group (or the wiring for a carbureted engine) that affects exterior lighting.

There is no fuse for the head/park light group - those circuits are fed straight from the battery and protected by a fusible link.

If you have no HL's or parking lights - and the HL switch is known good - check the fusible link near the firewall junction block.

 

[Thunder]

I went out and messed with it some more today.Ran a jumper straight from the battery to the low beam on one headlight. I have tail lights headlights and dash lights. When I try to switch to high beams I lose everything. I am assuming that is because power is hot to the low beams. I tried the jumper wire around the fusible link. NOTHING. Hooked the jumper back to the low beams and have power again. What am I missing?

 

[chengny]

Just off the top of my head - I'd say the dimmer switch is bad. Try pulling the harness connector off the switch and jumping the yellow to tan (should get just lows) and then yellow to light green (should get highs).

The actual switch is outside the column casing at the bottom LH side:

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[Thunder]

The correct answer was " D " None of the above.

Started studying schematics old and new. Truck has more fusible links than schematics show. Started tracing wires and removed the wire that was running from the battery to the junction block and connected it to the alternator. Hooked the battery up and expected to see smoke and melting wires. Instead I got lights, all of them. Everything is working like it should be on the two headlight system.

I then proceeded to tackle the job of converting to a 4 headlight system. Pain in the ASS. But to my surprise everything works great. Now all I have to do is come up with something custom to run the 4 turn signal/ marker light system. got a couple of ideas I'm working on.


Thanks for your help.


To the mods, will you set these guys up with some rep points. My head hurts too much to try and figure that out. Thanks.