Please confirm that these conditions were true when you performed this last test:

If so, you've proven that power is getting TO the switch and the switch is closing, yet power is not making it to the back of the truck. That means there's a fault along the BLACK with RED stripe wire going between the NSS and the backup lights. You'll have to investigate.

 

Yes all of those conditions are true, I just remembered there was a trailer brake plug that was spliced into the wiring harness that was removed. Maybe that is where its messed up. Time to go check it all out.

I just now checke the area where a trailer brake was wired in and it looked like a complete mess so I cleaned it up then checked the reverse lights and they still dont work so I checked how many volts I had right there- ZERO VOLTS. That means the problem is from the back of the cab forward. Im getting closer!

 

I've done some more investigating and i have determined that I am losing power to the reverse lights between the back of the fuse block and this green plug on the drivers side of the engine bay.
It leads to the wiring harness for the back of the truck.

(Black with Red Stripe tested 0 volts) Back-Up fuse has power to both sides of the fuse. (That is how I determined I am losing power between the fuse block and the green plug.

Would it be ok to unscrew the fuse block from the firewall to check wires or would I mess something up?

 

If you've got power to the WHITE with PURPLE stripe wire going TO the NSS at all, then all fuses are FINE. Do NOT pull back the fuse panel. You've got to stop going off on your own path against my instructions. It just adds more work and more questions that I have to answer.So far, you've determined that you have power TO the switch, and the switch appears to close properly. You found you do NOT have power at the sockets. Now you've indicated you don't have power at the green firewall plug. There are three explanations:1) There is a break between the NSS connector and the firewall plug.2) The measurement to show no power at the firewall plug was done incorrectly.3) The measurement to prove out the NSS was done incorrectly.My thoughts are as follows:1) Unlikely.2) Possible. Please explain how this was done (settings on the meter, where the probes were placed, shifter and key position, etc).3) Possible. You can eliminate the NSS as a possible culprit by unplugging the NSS and turning the key to ACC (shifter position doesn't matter). Jump the WHITE with PURPLE stripe and BLACK with RED stripe wires on the TRUCK connector together. The backup lamps should illuminate.Answer (2) and try (3). Nothing else.

 

FTE seems to be having issues and I can't space out my paragraphs. Hopefully you can still read it.

 

#2 i had my multimeter set on volts, high, I grounded to a screw on the firewall, put a nail in the clamp for the multimeter and checked the voltage to the black with red stripe.

Jumped the two wires as you said for #3 and the reverse lights illuminated.

 

That would indicate the NSS is bad, or out of alignment. It does not correlate with your continuity test, which indicated the switch was good and aligned properly. Both can't be true. Why do you think your multimeter test indicated the switch is good if all other tests indicate it is bad?

 

Prob didnt do the multimeter test right. Im not the best at electric stuff. Is it possible to clean up the NSS to get it to work again?

 

Probably not very easily. Looks like they're not cheap.