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'79 no tail lights or marker lights

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Old 05-19-2018, 07:47 AM
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onthe6ball
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Default '79 no tail lights or marker lights

fuse ok, power to the fuse, new headlight switch (no change from that) re did the ground at the left rear.
Old 05-19-2018, 09:31 AM
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TimAT
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The rear harness connector is right above the fuse block. Make sure it's secure and not partially disconnected or corroded.
Old 05-19-2018, 10:07 AM
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onthe6ball
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Originally Posted by TimAT
The rear harness connector is right above the fuse block. Make sure it's secure and not partially disconnected or corroded.
this fits the symptoms, since I can't find power at the rear. I can't find anything above the fuse block. 2 big bundles run back there. One from the left, one out to the right. I can't find any pictures of what I'm looking for, either. No connectors are visible in that area. Any other tips on where to look? BTW, dash lights are out, too, I don't know if that's related. First things first.
Old 05-19-2018, 10:24 AM
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DUB
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The rear wiring harness is right above or slightly hidden by your left kick plate.

DO you front side marker and park lights light up???

When you find the harness connector for your rear body wiring. You are looking forth BROWN wire. THAT is the wire that makes your running lights and side markers in the rear work.

If you still cannot find the connector for your rear body wiring..take out the left kick plate and you will see the harness coming from the rear of the car that is hidden/covered by the kick plate. The harness is under your carpet and door sill molding goes up by your hood release handle area.

DUB
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Old 05-19-2018, 11:32 AM
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Originally Posted by DUB
The rear wiring harness is right above or slightly hidden by your left kick plate.

DO you front side marker and park lights light up???

When you find the harness connector for your rear body wiring. You are looking forth BROWN wire. THAT is the wire that makes your running lights and side markers in the rear work.

If you still cannot find the connector for your rear body wiring..take out the left kick plate and you will see the harness coming from the rear of the car that is hidden/covered by the kick plate. The harness is under your carpet and door sill molding goes up by your hood release handle area.

DUB
Found the connector, 8 pin. I have a lot of digging to do. I get no power to the connector brown wire with headlights on. No marker lights, parking lights either.

Last edited by onthe6ball; 05-19-2018 at 11:33 AM.
Old 05-19-2018, 11:47 AM
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onthe6ball
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I was able to prove the harness to the rear. I bugged power to the brown pin going back, and the tail lights worked. wifey was watching them, didn't hear about side lights. Rules out rear harness and ground problems.
Old 05-19-2018, 11:49 AM
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dmaxx3500
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fuse box?
Old 05-19-2018, 11:51 AM
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onthe6ball
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intimidating, but it's the next thing back.
Old 05-19-2018, 11:54 AM
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The BROWN WIRE gets its power from the HEADLIGHT switch.

The ORANGE wire in your headlight switch connector gets its power from the TAIL fuse in the fuse panel.

Your dash light gets tis power from the DARK GREEN wire in the headlight connector when the headlight switch is ON.

This DARK GREEN wire from the headlight switch goes to your INST LMPS fuse at the very top of your fuse panel to the right of the flasher.

Your
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Old 05-19-2018, 02:20 PM
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The BROWN WIRE gets its power from the HEADLIGHT switch.

I think you saved my butt with this. I would have gone to the fuse block. Haven't been back at it yet. As soon as I find a diagram for the switch wiring, I'll dig further. Your response points to several electrical problems, and it's all at the switch. The switch is new, the problems are the same, so I'll check the connector to the switch carefully.
Old 05-19-2018, 03:03 PM
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DUB
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PULL the headlight switch and with a voltmeter...check the TAIL fuse on both sides and see if it is getting power.

Then do the same to the INST LTS fuse.

You can by-pass the headlight switch and run jumper wires to make the lights come on SO...you know you have a wiring problem further down the harness somewhere...it if it IS in the new switch.

12 gauge RED wire to the ORANGE wire should get your park lights to work.

12 gauge RED wire to the DARK GREEN wire should get dash lights to work...or at least you THEN can go down and verify IF the INST LTS fuse is getting power. The ONLY time the INST LTS fuse gets power is when the headlight switch is pulled.

DUB
Old 05-20-2018, 09:26 AM
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onthe6ball
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so far...headlight switch connected hanging out. Switch on, red to orange gives tail lights, running lights. switch on, no jumper, no tail/running lights.
red to green, no dash lights, some buzzer on.
Old 05-20-2018, 10:05 AM
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also...switch disconnected, no continuity from red to orange pins when switch is on. It's that way on both the old and the new switch. On the new switch, the rod does not seem to be latched.
Old 05-20-2018, 10:28 AM
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Switch hanging down...headlight switch is OFF. Do you have power on the ORANGE WIRE?

IF the answer is NO....then you need to check for continuity in that ORAGNE WIRE that is also ONE of the terminals in our fuse panel that holds your fuse. Disconnect the headlight switch from the connector. PULL OUT the TAIL fuse and use your ohmmeter an check BOTH of the terminals in your fuse panel. ONE of them is the one that is the ORABNGE wire and IF the wire is GOOD...you will have continuity .

AS for your dash lights. With you jumping the RED wire to the DARK GREEN wire and NO dash lights came on. You need to check the fuse. IF the fuse is OK. The perform the same test like you did on the TAIL fuse and see if your DARK GREEN wire from the headlight switch connector is going to the fuse panel is good.

You can have bad headlight switch...

DUB
Old 05-20-2018, 11:37 AM
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well, I think I found it, a problem I've never heard of. Looking into the tail fuse socket for the continuity check, half of the clip that holds the fuse is gone, no slot for the fuse. So...bugged a wire from the good (hot) side of the fuse holder and touched it to the orange wire on the headlight connector, switch on, and...ta da..everything lit up. next step, cobble a fuse into the middle of that wire, label it, and get inspected. Later, I guess replace the fuse panel or find a more secure cobble. I'll let you know about the temp fix in a while. You have been an enormous help, I never would have figured it out without your knowledge and advice.
Old 05-20-2018, 11:45 AM
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That broken terminal can be repaired CORRECTLY if you choose to take the time and effort to do so. No need for an entirely new or used fuse panel.

And it is not the first time that I have run across a broken fuse terminal.

Yes..running remote location for that fuse is 'do-able'..as you know.

Just saying.

DUB

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