tail light issues
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tail light issues
i have a 79' F-150 custom, and my tail lights, and rear turnsignals quit working but my brake lights and hazards work fine as do my head lights and front turn signals.... does anyone know whats wrong? any help would be great thanks so much
Fleet Mechanic
Joined: Aug 2005
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From: Hartford, AL
Turnsignal and rear lights on same circuit I believe. Hazards and brake lights are on a different circuit. Check your wiring at the back to see if you are getting power. Green wire should be RH rear lamp and Marker, Yellow/Black should be LH Rear lamp and Marker. Green/Wht is LH Turn Signal and Dash Indicator, and Wht/Black RH Turn Signal and Dash Indicator. Check you grounds at the rear lights. You have to have a bad ground if the front signals are working. Let us know if you have 12v on the green wire and yellow/black wire in the back with lights on, and also the green/wht, and wht/blk with the turn signals activated.
Fleet Mechanic
Joined: Aug 2005
Posts: 1,462
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From: Hartford, AL
A cheap $3 voltage circuit tester will do if you don't have voltmeter. It wouldn't be a fuse if fronts work. You are losing power and or ground somwhere between the turn signal switch in the column and the rear lights, and the wires go straight from the column to the back albeit through a couple of plugs (as bullit390 said good to check those). Start at the taillight and work back to the color of wires coming out of the column to narrow down loss of current...using the colors I suggested above. You need at least a circuit tester (you know the one that lights up if there is voltage) to help diagnose electrical problems.
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there dosnt appear to be a connector by my gas tank, also i didnt see any conectors from the lights to the cab.... i had a hitch instaled on the truck at u-haul over the summer could that do it??
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and i noticed they didnt tape the connections, they just used the quick connects like the wire tap things...
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Well, the connector at the back of the truck is there to disconnect the frame harness from the bed harness. That way you can just lift the bed off and not have to worry about taking out all the lights.
If indeed U-Haul monkeyed with the wiring that would definatley look there first.
The dash lights are not directly related, although the light switch is many times the culprit, try turning the **** back and forth and see if it makes the dash lights do anything.
Be patient, these problems will get handled.
Josh
If indeed U-Haul monkeyed with the wiring that would definatley look there first.
The dash lights are not directly related, although the light switch is many times the culprit, try turning the **** back and forth and see if it makes the dash lights do anything.
Be patient, these problems will get handled.
Josh
Fleet Mechanic
Joined: Aug 2005
Posts: 1,462
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From: Hartford, AL
Follow that rear harness up to the cab. My connector for the rear harness is on the engine side of the firewall in the engine compartment...but, I would definitely check all of the wiring u-haul did and would chunk those twist connectors and at least get crimp on connectors or better yet solder and shrink wrap the connections. I bet that is where the problems exist for the rear. The power for the interior lights comes from the blue/red stripe wire from the headlight switch, it then routes inline through the fuse panel...should be a 3amp fuse in the panel and also routes through to the dome lights and door jamb switches. Problems there could be the fuse, the headlight switch, or bad ground at the door jamb switches...they tend to get a bid corroded. Like I said go to your local parts store and pick up a $3 circuit tester and start at the Uhaul wiring, and as mentioned be patient. You can find and fix the problem.
Post Fiend
Joined: Jul 2004
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From: Northern California
If U-haul messed it up, then I would take it back to U-haul to correct it or at least get your money back.
Especially if it hasn't been too long ago, and your state law disallows incidential and concequential damage disclaimers.
Some of the people at U-haul do not impress me.
Especially if it hasn't been too long ago, and your state law disallows incidential and concequential damage disclaimers.
Some of the people at U-haul do not impress me.
Post Fiend
Joined: Jul 2004
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From: Northern California
Sounds like you need a light switch, along with the wiring problems you have.
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well its not the u-haul wiring cause i have no power back there, not even before the u-haul wiring... the grounds all apear good and are not corroded, also the rear light connector(or disconect, located on my firewall apears to be good with no corrosion. could the light switch cause just the lights in the rear to quit working??