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Back-Up lights don't work

731 Views 1 Reply 1 Participant Last post by  adamg69
I am slowly putting my 70 MACH 1 back together, and I decided to install new back-up lights. I cannot get them to work. They never have worked every since I owned the car, and I did not think that replacing them would fix it. Where should I begin on tracing the problem?

The car is an automatic with FMX. It has a new neutral safety switch also. I am not getting any juice at the rear harness, and I do not think it's getting any juice at the neutral safety switch either when I put it in reverese. Any suggestions?

Jerry P.
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I don't know how the switch set up is on an auto but the harness from the firewall outward is the same on an auto/manual. You should see a connector there that has two sets of contacts, one set for the backup and one set for the neutral safety switch (ie 4 connectors, 2 recessed and 2 exposed in a square shaped connector). On my set up the neutral safety set are shorted together, the reverse set has 12V constant on one that goes down to the switch, when the switch completes the circuit it puts 12V juice out to the backup lights. Try and make sure you have 12V at this connector first, you shoul be able to figure out which is which, if none have 12V (ignition on) then you have found at least one part of the problem. If you have 12V you need to start looking for a leak, I'd try disconnecting the lights from the harness in the trunk first if that is the case, one st of my lights wiring was badly worn and shorting also. Hope this helps a little.

69 Sportsroof, 351C, 4spd toploader, Restomod BOSS 429 clone - the one and only (?) 1969 BOSS 351
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