Back up lights not working

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Back lights not working, checked all fuses=good, replaced NSS, still nothing, if I unhook the 4 wire plug at the firewall and use Power probe to put power to the black wire w/pink tracer they work. Can not figure out where power comes into circuit. Should the black/pink have power with key on? 72 Fastback 351C w/FMX trans. ps. wipers & washers work and so does cig lighter. I am stumped! Any one have any ideas?

Thanks in advance.

TFA

 

midlife

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No, the black/pink wire is the return wire for the backup lamps; the white/pink wire should be hot when the key is on ACC.

 
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No, the black/pink wire is the return wire for the backup lamps; the white/pink wire should be hot when the key is on ACC.
Does it feed from the ignition switch?

 

midlife

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It feeds from the top-left most fuse, shared with the radio and part of the wiper system.

 
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It feeds from the top-left most fuse, shared with the radio and part of the wiper system.
So if the wipers/washers and radio work the wire must be open from there to plug at fire wall. Will check that out.

Thanks for your help.

TFA

 

72HCODE

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the floor shifter could be out of adjustment also.

move the shifter back and forth slightly out of position and see if the lights come on.

the shifter gets sloppy with age so you may need to readjust the trans to floor shifter bracket.

 
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the floor shifter could be out of adjustment also.

move the shifter back and forth slightly out of position and see if the lights come on.

the shifter gets sloppy with age so you may need to readjust the trans to floor shifter bracket.
I moved the lever slowly on the new switch before I mounted it and I did not get them to work with the ignition switch on.

 

Danno

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I had the same problem, and found that the engine side of the plug that connects to the NSS plug, the white wire coming out of that plug that should be hot and send power to the lights when the lever was in rev, was not. What I did will make some people cringe but I cut that white wire and spliced a wire about 3" from the engine connector and ran it directly to the fuse box and connected it with a fuse tap.

Guessing that that wire should have 12 volts on it waiting for the NSS switch to complete the circuit and turn on the lights, I took that portion of the engine harness out of the picture and have the 12 volts coming directly from the fuse box.

I did this over a year ago and it has worked fine but had to go out look at it again to refresh my memory. I hope i havn't confused you.

The alternative would be to either replace the harness or unwrap miles of tape to find the broken wire, neither of which I want to do with the engine installed.:-/

 

midlife

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I had the same problem, and found that the engine side of the plug that connects to the NSS plug, the white wire coming out of that plug that should be hot and send power to the lights when the lever was in rev, was not. What I did will make some people cringe but I cut that white wire and spliced a wire about 3" from the engine connector and ran it directly to the fuse box and connected it with a fuse tap.

Guessing that that wire should have 12 volts on it waiting for the NSS switch to complete the circuit and turn on the lights, I took that portion of the engine harness out of the picture and have the 12 volts coming directly from the fuse box.

I did this over a year ago and it has worked fine but had to go out look at it again to refresh my memory. I hope i havn't confused you.

The alternative would be to either replace the harness or unwrap miles of tape to find the broken wire, neither of which I want to do with the engine installed.:-/
:jawdrop::atomic::nutkick: *G*

 

naa10104

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Hello,

Have you done anything with your radio wiring lately ? This wiring is part of the NSS circuit.

I had the same problem, and found that the engine side of the plug that connects to the NSS plug, the white wire coming out of that plug that should be hot and send power to the lights when the lever was in rev, was not. What I did will make some people cringe but I cut that white wire and spliced a wire about 3" from the engine connector and ran it directly to the fuse box and connected it with a fuse tap.

Guessing that that wire should have 12 volts on it waiting for the NSS switch to complete the circuit and turn on the lights, I took that portion of the engine harness out of the picture and have the 12 volts coming directly from the fuse box.

I did this over a year ago and it has worked fine but had to go out look at it again to refresh my memory. I hope i havn't confused you.

The alternative would be to either replace the harness or unwrap miles of tape to find the broken wire, neither of which I want to do with the engine installed.:-/
:jawdrop::atomic::nutkick: *G*
 
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I had the same problem, and found that the engine side of the plug that connects to the NSS plug, the white wire coming out of that plug that should be hot and send power to the lights when the lever was in rev, was not. What I did will make some people cringe but I cut that white wire and spliced a wire about 3" from the engine connector and ran it directly to the fuse box and connected it with a fuse tap.

Guessing that that wire should have 12 volts on it waiting for the NSS switch to complete the circuit and turn on the lights, I took that portion of the engine harness out of the picture and have the 12 volts coming directly from the fuse box.

I did this over a year ago and it has worked fine but had to go out look at it again to refresh my memory. I hope i havn't confused you.

The alternative would be to either replace the harness or unwrap miles of tape to find the broken wire, neither of which I want to do with the engine installed.:-/
I was thinking of doing that but really don't want to cut the OEM harness if I don't have to. I have ordered a wiring diagram for CJ pony to review the complete circuit. Wiring problems are always a pain in the butt.

Thanks for your input.

TFA

 

Danno

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I had the same problem, and found that the engine side of the plug that connects to the NSS plug, the white wire coming out of that plug that should be hot and send power to the lights when the lever was in rev, was not. What I did will make some people cringe but I cut that white wire and spliced a wire about 3" from the engine connector and ran it directly to the fuse box and connected it with a fuse tap.

Guessing that that wire should have 12 volts on it waiting for the NSS switch to complete the circuit and turn on the lights, I took that portion of the engine harness out of the picture and have the 12 volts coming directly from the fuse box.

I did this over a year ago and it has worked fine but had to go out look at it again to refresh my memory. I hope i havn't confused you.

The alternative would be to either replace the harness or unwrap miles of tape to find the broken wire, neither of which I want to do with the engine installed.:-/
:jawdrop::atomic::nutkick: *G*
Yeah, I might deserve that, but it works and a man on horseback would never see it. I know what and where the problem is, it is hidden and I have working back up lights and I do intend to address it in the future. This car is far from a trailer queen.

 
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Ok, I found my problem, got looking under dash and found a flat 2 plug female connector behind radio with 2 white wires with pink tracers going into one port of connector and a light blue w/red tracer in other port but not plugged into any thing, traced the white w/pink wires and found one that was cut and not connected to anything, connected them together with a heat shrink butt connector and bingo the back up lights came on! I don't know what would or should be plugged into that connector. The oem AM radio is long gone so maybe for it. So any way now my circuit is complete with out splicing any power wire from fuse panel to power up the circuit. YES!!

TFA

 

midlife

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Yes, that plug was for the radio: power and lamps. Good job!

 
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