Back up lights /NSS (again)

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brodertr

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My Car
73 modded convertible
Got a 73 Convertible that's ready for the road EXCEPT - no back-up lights.

Scoured all the posts but found something I didn't expect.

First off - bulbs are good, no power to sockets, fuse ok. 

Crawled under, planning to check out power to NSS, expecting to have to change out the NSS. First thing I noticed was the dangling connector with nothing attached.





Not sure, but is this right? Seems like SOMETHING should connect!

Also, looks like the NSS and the linkage is new-ish and has been replaced recently so that sorta steers me away from that.



So before I go tearing things out - is this the right NSS? And what does that connector attach to? Is this why I have no back-up lights?

Advise on where do I go from here?

BTW - car started out as a 73 base model, auto transmission.

 
That blue plug is a seat belt warning signal that is also part of the NSS/BU switch. You need to look for a black 4 pin square plug.

 
In your second picture, it looks like the neutral safety switch/backup light switch connector is next to the blue connector.

Even though it starts, the NSS may not be properly adjusted or the backup portion of it may be bad. The black with red stripe wires are for the backup lights.

 
I feel your pain. My back up lights don't work either. Just changed the NSS, no change. Maybe its the stupid brake switch again. Damn thing is finicky and a bitch to get to.

 
Thx guys - will root around the engine well and see if I can find lost connector.  IF I can't find a plug - [seat belt warning] (which is strange cuz I do have seat belt warning light {no bulb currently} above glove box and connected beneath passenger seat), does it have to be connected /jumped to complete the BU light circuit? Or can I just ignore it and let it hang, focusing instead on the BU light connection?

 
The connector for the NSS that controls the BU lamps and the starter interlock has four wires

Red w/light blue stripe (2 of) - this is the starter interlock circuit

White/purple stripe - power in to NSS for BU lamps

Black/pink stripe - power out from NSS to BU lamps

With the ignition on, verify you have 12V at the vehicle side of the connector on the White/purple stripe wire. If not, check your fuses, it's #6, 15 amp, which also powers the radio, w/s washer and turn signals. If you have power, jump the white & black wires to diagnose the NSS and the backup lamps themselves. With the wire jumped, check for power at the sockets in the tail lamps. Most times, the problem is a bad ground, bad sockets or bad bulbs. Once you get everything working, plug the NSS back into the harness. If you still have no BU lamps, then it's the NSS and it either needs to be adjusted, cleaned or replaced.

 
The connector for the NSS that controls the BU lamps and the starter interlock has four wires

Red w/light blue stripe (2 of) - this is the starter interlock circuit

White/purple stripe - power in to NSS for BU lamps

Black/pink stripe - power out from NSS to BU lamps

With the ignition on, verify you have 12V at the vehicle side of the connector on the White/purple stripe wire. If not, check your fuses, it's #6, 15 amp, which also powers the radio, w/s washer and turn signals. If you have power, jump the white & black wires to diagnose the NSS and the backup lamps themselves. With the wire jumped, check for power at the sockets in the tail lamps. Most times, the problem is a bad ground, bad sockets or bad bulbs. Once you get everything working, plug the NSS back into the harness. If you still have no BU lamps, then it's the NSS and it either needs to be adjusted, cleaned or replaced.
Click to expand...
Thx, will give it a try next week when I get back in town.

 
The connector for the NSS that controls the BU lamps and the starter interlock has four wires

Red w/light blue stripe (2 of) - this is the starter interlock circuit

White/purple stripe - power in to NSS for BU lamps

Black/pink stripe - power out from NSS to BU lamps

With the ignition on, verify you have 12V at the vehicle side of the connector on the White/purple stripe wire. If not, check your fuses, it's #6, 15 amp, which also powers the radio, w/s washer and turn signals. If you have power, jump the white & black wires to diagnose the NSS and the backup lamps themselves. With the wire jumped, check for power at the sockets in the tail lamps. Most times, the problem is a bad ground, bad sockets or bad bulbs. Once you get everything working, plug the NSS back into the harness. If you still have no BU lamps, then it's the NSS and it either needs to be adjusted, cleaned or replaced.
Click to expand...
Thx, will give it a try next week when I get back in town.
Click to expand...
I had the same problem, and my solution wasn't the prettiest, but it worked. After extensive troubleshooting and NSS adjustments,

I found I had no power on the vehicle side of the harness, so I spliced a wire from the fuse to the power in wire on the switch. I now have 12v waiting at the bu light switch, and the lights work. The other alternative was to try to see where I lost power some where in that harness that runs all over the engine bay and this was a "quick fix. I intend to chase wires sometime, but not today, LOL!!! :shootself:

 

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