Reverse lights are not turning on when transmission is put into reverse

1997 FORD F-150
232,000 MILES • 4.6L • V8 • 2WD • AUTOMATIC
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NICKBAR87
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My Reverse will not turn on when in reverse. Have checked bulbs, neutral safety switch, and wire continuity from bulb all the way up to harness in engine bay. Still do not have power to bulbs when in reverse, and I am now at a stand still. Is there another fuse or relay that controls power to reverse lighting system?
Dec 11, 2016 at 7:12 PM
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CJ MEDEVAC
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Lets check for power at fuse # 5 here is a guide to help you and the reverse light wiring diagrams so you can see how the system works and the fuse locations as well.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Check out the diagrams (Below). Please let us know what you find.
Dec 11, 2016 at 7:41 PM
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NICKBAR87
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The transmission range sensor is the same thing as the neutral safety switch, which was replaced a few months back. I have already checked that and replaced once again with no luck on the lights working.
Dec 11, 2016 at 7:46 PM
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CJ MEDEVAC
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The rest of the diagram?

Such as the grounds (locations given)

Power at the fuse location?

Problem with the trailer back-up relay?

Connectors needing dielectric grease?

Connectors with melted plastic/ pins not making contact?

Unplugging the lights (in various places along the way and introducing power using long jumper wires to verify the housing/ lights do work?

Gotta be in here!

Got a buddy thinking on it too?

The Medic
Dec 11, 2016 at 8:04 PM
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NICKBAR87
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I have checked continuity on power and grounds all the way up to wire harness in engine bay located under air intake. Checked all connections, nothing broken. Checked trailer/tow light fuse and no problem. All the lights in the taillight housing work except for reverse lights. Unless there is a fuse somewhere for just reverse that I cannot find. I cannot a blown fuse anywhere.
Dec 11, 2016 at 8:27 PM
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NICKBAR87
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So now I have replaced a few parts on the electrical side of these lights and now I am having an issue where there is constant power to my reverse lights along with too many amps flowing through the fuse.(I know it is a 15amp fuse, but I am getting 24/25 amps at the fuse).
Dec 12, 2016 at 8:23 AM
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STRAILER
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Hey NICKBAR87,

It sounds like you have a wiring harness problem. Use the a test light to find see why the power is continues and unplug the neutral switch first to see where the power is coming from.

Please let us know happens so it will help others.

Best, Ken
Dec 12, 2016 at 10:33 AM
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NICKBAR87
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I found the issue, there is a connection problem in the fuse box under the dash. There was continuity between the power wire and negative wire. I wound up having to run a fusable link between a fuse that has power with the truck running and the wire for the reverse lights just before it passes through the fire wall.
Dec 12, 2016 at 11:16 AM
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STRAILER
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Nice work, we are here to help, please use 2CarPros anytime.

Best, Ken
Dec 12, 2016 at 4:00 PM