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Old 09-27-2011, 11:33 PM   #1
69heavychevy
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No headlights, parking and tail lamps work

I decided to clean up my wiring harness. I was already running the relay mod and HID's. Since I have single beam HID's and have no use for the high beams, I decided to get rid of all the 14LG wiring (high beams) and leave only the 18 LT wiring (low beam). Then neatly wrapped my whole wiring harness in electrical taped hooked everything up, cranked her up, turned light on and only the headlights didnt come on. Suspecting the headlight switch, I went to the parts store and tried a new one but still nothing.

I did some checks and...
1. domelight doesnt work anymore either
2. terminal 30 on the relay has 12.45 volts
3. terminal 87 has .40 volts
4. and terminal 86 has 0 volts

Any help would be appreciated, by the way heres how I re-wired my headlights
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Old 09-28-2011, 12:15 AM   #2
jhwkns
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Re: No headlights, parking and tail lamps work

Check your dimmer switch.
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Old 09-28-2011, 01:03 AM   #3
69heavychevy
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Re: No headlights, parking and tail lamps work

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Originally Posted by jhwkns View Post
Check your dimmer switch.
so power runs from the headlight switch then through the dimmer switch and onto the headlight?? I figured they were independent circuits...I guess I'll give that a check tomorrow as well.
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Old 09-28-2011, 08:03 AM   #4
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Re: No headlights, parking and tail lamps work

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Originally Posted by 69heavychevy View Post
so power runs from the headlight switch then through the dimmer switch and onto the headlight?? I figured they were independent circuits...I guess I'll give that a check tomorrow as well.
Yes.
In a stock system you turn your headlights on and 12 volts goes from the headlight switch to the dimmer. Three wires connect at the dimmer. One from the headlight switch and one each to high and low beam circuit.

Pull the connector off the dimmer switch, turn the headlights on at the switch and verify that you have 12 volts on one of the wires. If you don't have 12 volts on one of the wires the problem is the headlight switch or the wires between it and the dimmer.

If you have 12 volts on one of the wires jump that wire to either of the other two connectors. One will turn on high beams, one will turn on low beams. If it doesn't your problem is between that connector and your relays.

Those connections get green and furry in most areas outside the desert southwest because you get in with wet feet, etc and the connector sees moisture.

If this is your problem go to NAPA and purchase three new "Packard type 56" female connectors. (NAPA part number 725147). If your local NAPA makes you buy a full box of 50 you should consider it. You can fix just about every female connector on your truck with these.

Repair the connector by inserting a small, flat blade screw driver into the connector releasing the tab that holds it in place. MAKE NOTE OF THE POSITION OF EACH WIRE BEFORE REMOVING THEM. Repair the wires, insert back into the connector, plug in the connector, and you're good to go.
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Old 09-28-2011, 12:38 AM   #5
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Re: No headlights, parking and tail lamps work

I don't know that specific relay, but aren't you supposed to be feeding #86 with 12v? It looks like you're not energizing the relay.
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Old 09-28-2011, 12:39 AM   #6
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Re: No headlights, parking and tail lamps work

Can you post a schematic of the relay?
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Old 09-28-2011, 12:55 AM   #7
69heavychevy
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Re: No headlights, parking and tail lamps work

I'm not sure if it has a schematic printed on the relay, I'll have to look tomorrow. But its the old style dual mopar relays that came hooked on a bracket. Its just a plain standard 12 volt 40amp relay, I think lol.
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Old 09-28-2011, 01:04 AM   #8
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Re: No headlights, parking and tail lamps work

I agree don't overlook the dimmer switch if the relay is hooked up correctly.
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Old 09-28-2011, 09:05 AM   #9
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Re: No headlights, parking and tail lamps work

How you going to pass inspection with no high beams?
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Old 09-28-2011, 02:30 PM   #10
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Re: No headlights, parking and tail lamps work

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How you going to pass inspection with no high beams?
Its registered as an antique, no inspection required...
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