Tail Lights Still Staying On

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Re: Tail Lights Still Staying On

Post by FordTruck »

fordman wrote:check the back of the fuse box. maybe something has broken off and is feeding back through the brake lights.
Will do I don't know what I'll do if I need a different fuse block.
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Re: Tail Lights Still Staying On

Post by fordman »

they sell generic ones at the parts stores you can even add more circuts if you wanted to a new one.
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Re: Tail Lights Still Staying On

Post by FordTruck »

fordman wrote:they sell generic ones at the parts stores you can even add more circuts if you wanted to a new one.
But how do I take all the circuts off my box and add them to a different one? That would be nice to have more circuts too.
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Re: Tail Lights Still Staying On

Post by fordman »

the wires are hooked into a connector on the original box. the connector is riveted into the box prongs. you could just drill out the rivets. or cut the wires off the connectors.it would depend on how much wire you need to reach each new position on the newer box.
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Re: Tail Lights Still Staying On

Post by l1k2gadd »

Check to make sure all of the bulbs are DUAL ELEMENT bulbs with two contacts on the bottom of them. I had a single element bulb in a socket on one side of a vehicle feed power across the two terminals in the socket and cause a back-feed.

Alaso, if you have installed an after-market radio to your truck be sure you haven't twisted the radio power feed wire as a hot wire to the blue-with-red-stripe interior light wire. That can also create a back-feed through wiring in a vehicle and cause multiple lamps to light when the key is turned on.

Does this only happen after the key is turned on or are the lights on all the time, with or without the key?
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Re: Tail Lights Still Staying On

Post by FordTruck »

l1k2gadd wrote:Check to make sure all of the bulbs are DUAL ELEMENT bulbs with two contacts on the bottom of them. I had a single element bulb in a socket on one side of a vehicle feed power across the two terminals in the socket and cause a back-feed.

Alaso, if you have installed an after-market radio to your truck be sure you haven't twisted the radio power feed wire as a hot wire to the blue-with-red-stripe interior light wire. That can also create a back-feed through wiring in a vehicle and cause multiple lamps to light when the key is turned on.

Does this only happen after the key is turned on or are the lights on all the time, with or without the key?
I'll check the bulbs. The problem started right after the cab swap because before that it didn't do that. It dosen't matter one the key as long as there plugged in there on :doh:
"Flyin High On Caffine And Copenhagen" R.I.P Chris LeDoux

60 Mercury Comet
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72 Ford F100 on 79 4x4 SWB frame
77 Ford F250 "lowboy" 4x4
09 Harley Xl1200c
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Re: Tail Lights Still Staying On

Post by l1k2gadd »

If you reused the original wiring harness when you did the cab swap there shouldn't be anything different between the two trucks. If you are trying to mix and match wiring harnesses you might run into differences in plugs and connectors. Be real careful to match wiring colors on plugs. Make sure you didn't plug any of the harnesses into a circuit in the truck that is "always hot" like the fuel gauge feed or interior lights plugs under the dash.

Unplug each wire going to the back of the truck until the lights go out. When you find the one that is causing the problem trace it back to the under dash harness to see where it is feeding from.

Make sure no wires got pinched between any body panels when you set the new cab in place. Be sure none have gotten "skinned" by scraping any sharp metal edges, as these, when brushing up against one another can cause what is called in the telephone industry as a side-cross (a hot from one wire touches another causing it to be hot or energized).
Too many projects, too little time, but.. lovin' it!
2-1966 Mustangs (one 289-2V and one 200 6 Cylinder),
1-1990 7-Up 5.0 Mustang LX Convertible (second one),
1-1990 7-Up 5.0 Mustang LX Convertible (third one, for parts only)
1-1990 7-Up 5.0 Mustang LX Convertible (fourth one, best of the bunch).
1-1992 "FEATURE" 5.0 Mustang LX Convertible (only one)
1-1993 "FEATURE" 5.0 Mustang LX Convertible (one of the yellow ones)
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