roof lights

[magnethead]

Does anyone know which wire the exterior roof clearance lights go to off the light switch? My roof lights aren't working and they aren't getting any power. Already checked the grounds.

I took my MM and stuck one probe in the negative bulb connecter, put the ground clip back on, then put the other probe on one of the screws holding another light down, and it had continuity. So i kept the negative probe where it was and put my positive probe in the light connector and turned the lights on, and it read 0.000 volts.

[piecesparts]

The cab lights are part of the PARK light circuit. I would have to go into the shop manual wiring diagram at my home to find out where it ties in. Do you have the Park lights illuminated? Is there a seperate fuse on your panel? If everything is working, then there is a break in the wiring, somewhere. You could run a new wire up the post to the circuit and splice it to the park circuit, if you have to.

[magnethead]

i check it with the headlights and everything on. Not sure if those lights use their own fuse. Headlights were on, turn signal/parking lamps were on, both lights on the left side fender were lit up, and i was getting 11 volts at the passenger side fender (bad bulbs). So only the cab lights weren't working.
thanks

[boxrodz]

Like piecesparts said, the roof marker lights run off the tail circuit. From what I can tell, the positive feed for the left marker light comes from terminal 3 on the light switch (Black wire). Then from the left marker light, the postive feeds the next marker light and so on. Each marker light has it's own ground. And, since you tested each ground I would first check the positive feed to the left marker light. If you have no voltage there, then check terminal 3 on the light switch that feeds the roof marker lights. My guess is that you may have a bad connection between the light switch and the left marker light.

[magnethead]

I didn't test each ground, just the right side one. Since i registered no voltage there and all 5 didnt work, i based that all 5 have the same problem.

I'll check that wire next chance I have and see if i'm getting 12 volts.

[89 crew]

something to I ran into a while back was a spotlight someone had mounted in the post next to the windsheild. when they did they drilled through the hot lead going to the lights. Don't know if it will apply to yours. Hope it helps!

[magnethead]

dont think that applies here. My dad says they worked even with broken lenses as recent as a couple years ago...so maybe a fuse blew or a wire nut and connection came loose?

[89 crew]

that is very possible. where the lenses are broken if water caused a short while they were on it could blow the fuse. If it did you wouldn't have any tail lights. do they work?

[magnethead]

yea all 4 corner lights work...

[89 crew]

then that makes it simple. your choices are
1 bad connection at switch.
2 bad wires between switch and first socket.(you might try a jumper to first socket to make sure rest work)
3 where the lense has been leaking how is the socket corrosion?
4 I'm down to all 5 bulbs being bad! not likely but should be visable!

[magnethead]

itt's not my bulbs. I checked it with a DMM going from a known ground to the power side of the plug. I'll try the jumper idea, didn't think of that one.

the lenses (except for far left) are completely busted off..some have a ring of lense left at the bottom and some don't even have that. The contacts looked good, the ground tat i looked at was rusty but still had good continuity. I'll check all 5 grounds.

[magnethead]

I knew i had a picture somewhere..



(and since i'm sure you're wondering, yes that tint is dark enough. It's maximum legal on all 3 back windows, and I plan on, within the next year, getting the front doors (not windshield) done to 5% on the safe side of max legal

[magnethead]

i suck at drawing so here's an attempt at explaining it..

In the very top right connector, there are 2 ORANGE wires. In the connector below that (middle right), there is no wire. In the bottom right, there is also no wire.

In the 2 middle connectors, the top wire is brown and the botom one is blue.

The top left connector has a silverish wire, below that is green, below that is red, and left of that is white.

[magnethead]

[magnethead]

anyone?

[89 crew]

I missed your question. If you are looking to hot wire the lights to see if they work skip the loom and run from battery hot to first light. If you are trying to rewire I would start at the switch. turn the tail lights on and see which wire goes cold when you turn them off. make sure you don't get dash light circut! If that doesn't answer I need a better idea of the question.

[magnethead]

where do the roof lights tie into the wire going from the front amber lights to the rear fenders? I'd like to have the roof lights working (along with all 4 of my fender lenses installed) by the 25th. I followed the loom from the front ambers back to where they go into the back of the fuse block, but lost them there. I can't see where any of the wires go from the switch. I was told the roof lights are a black wire- theres no black wire going to the switch. Closest one is speckled silver or brown.

I'd rather not hard wire it, but if i have to, i can run a relay or get a switch panel and have extra switches (pro stock style) for diferent functions.. roof lights, bed spot light (cargo light), forward spot light in grille, ect.

[piecesparts]

The cab marker lights are black wires, according to the wiring diagram in my factory shop manual. There is a grond wire for each light and then there is a black wire (noted as .8 BLK - 45) going to the light switch (Term 3 circuit 9). This wire appears to tie into the side marker light wire wich is a ( .8 brown wire --.8 brn-9) on the circuit to the light switch. Take a look at your light switch and see if there is a brown wire coming off of it and then power it up and down and see if that is what you want. I would tie onto that wire if it was me.

[magnethead]

yup i have a brown. Would you have a clue as to where the existing wire runs/comes out of the A-pillar so i can find and meter it to see if i have signal? Otherwise, how can I run a new wire down the A-pillar since theres a good ~2" gap between internal and external cieling layers?

[piecesparts]

Look along the side panel just behind your dash on the driver's side. You may have to look up behind the actual dash itself and see if you can locate the black wire that is connected to the cab lights. Once you find this wire, then check it out to see it it is grounded out or broken. If you have to run a new wire, you might be able to use this one aas a pull wire to get the other one through the "A" pillar. It that doesn't work, then pull your dome light and run the wire from the front of the cab back to the dome light hole and then acroos to the "B" pillar area and then down to behind the driver's door. This is just a little out of the way, but it can be done without a lot of pain.

[magnethead]

i'll look up there and see if I can find it. i'll meter it from positive to ground and see if my dad might have ever grounded it accidentally (black being power..odd).

(and i think that picture solves the mystery of not having lights over my 3 minor gauges)

[piecesparts]

See the buzzer in your picture, I sent mine to trashcan Hell---many years ago. Put a bulb into the hole

[magnethead]

my buzzer don't even work, but the one in my friend's 84 does it is annoys the hell out of both of us.

IO have the driver side sun visor off, part of the trim around it off, half the loom under the dash untaped, and just finally found the wire under the hinge of the hood, and now i'm trying to figure out where it goes thru the firewall.

[magnethead]

Ok, this ain the least of my concerns. I found out why m dash lights don't work great, but still aint found the roof light wire..

doesn't it help when all the wire connections actually stay tight? Now i need to somehow get at that loom between th gauges and the dashpad and re-do some connections- I jiggle a couple wires and my exterior lights die. Jiggle again, they work....

[magnethead]

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