When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Just so I'm not confused...or maybe I am. The 2 wires coming out of the NSS, black/red say on the wiring diagrams backup lights...In my head I'm asking where are they getting the power for the lights from though. What complicates this is my truck is a fresh wiring job - there was no wires at all and connectors so in many cases, I'm just wiring straight to termination points. Do each of those wires go to each of the reverse lights and it gets power through the NSS?
You NSS should have 4 wires.
1 set for the starting circuit - 1 wire should have power when key is turned to start and that goes thru the NSS and out to the solenoid.
This switch should only be closed when in park & neutral and open all other times.
The other set of wires for the backup lights.
Normally the backup light switch takes 2 wires, 1 with power with key on and the other out to the lights.
The switch is a normally open on / off switch and when the shifter is put into reverse it closes the switch sending power to the backup lights.
With a test light it should not be hard to tell what does what.
Dave ----
According to my wiring diagram for a 77 f series.... there is a black-red stripe that runs from the fuse block to the Neural Safety Switch. this wire feeds the power. then to confuse things even further.... there appears to be another black-red stripe wire that runs out of the neutral safety switch that feeds power to the backup lights.
According to my wiring diagram for a 77 f series.... there is a black-red stripe that runs from the fuse block to the Neural Safety Switch. this wire feeds the power. then to confuse things even further.... there appears to be another black-red stripe wire that runs out of the neutral safety switch that feeds power to the backup lights.
This is from a 76.
Again the NSS / backup switch is just a on / off switch.
That wire from the fuse box is power in and the other same color wire is out to the backup lights out back.
To test make sure the fuse box wire has power and run a jumper between the 2 wires and the lights if good should come on.
It is that simple
Dave ----
Again the NSS / backup switch is just a on / off switch.
That wire from the fuse box is power in and the other same color wire is out to the backup lights out back.
To test make sure the fuse box wire has power and run a jumper between the 2 wires and the lights if good should come on.
It is that simple
Dave ----
yep... do what Dave is saying. Jump it and have someone check the lights. Keep chasing it... you will find the issue.
This is not an issue, this is all new wiring. I did talk to the harness manufacturer - they do not include a fuse to NSS wire and NSS to backup light wires so I'll just make those.
Just so I'm not confused...or maybe I am. The 2 wires coming out of the NSS, black/red say on the wiring diagrams backup lights...In my head I'm asking where are they getting the power for the lights from though. What complicates this is my truck is a fresh wiring job - there was no wires at all and connectors so in many cases, I'm just wiring straight to termination points. Do each of those wires go to each of the reverse lights and it gets power through the NSS?
One is hot when the key is on, and the NSS completes the path to the lights through the other to out back when adjusted correctly and the truck is placed in reverse. The wire to the BU lights splits near the rear bumper, and BU lights ground to the truck body.
Originally Posted by w951wxj
This is not an issue, this is all new wiring. I did talk to the harness manufacturer - they do not include a fuse to NSS wire and NSS to backup light wires so I'll just make those.
Don't know what you have, but my '77 has a fuse box under the dash to the left of the steering, and fuse #11 is a 15 amp fuse that protects the BU lights and the windshield washer pump circuits.
Bear it sounds like he used an aftermarket harness to rewire his truck, see post #6, and we all thought it was the factory harness he was talking about.
Still easy to wire, The NSS switch is 2 switches in 1
The start signal from the IGN switch to the NSS side that will only let power pass when in P or N and then out to the starter solenoid.
For the back up lights any wire from the fuse box that has power with key in run to the NSS that only lets power pass when in R and a wire back to the rear lights.
That is how the factory did it just in the factory harness.
Dave ----
So in simple terms - one of my wires out of the flat connector at the NSS (skipping NSS wires - know where they go) one has to go to the fuse and the other out to lights...There is on the new NSS switch, since I'm not positive my original will still work, the new switch has a 5th wire coming out that is confusing me as to where that has to go or is that just a "just in case you need it" type wire. Sorry about the questions - this truck was a haul out of a barn and try to re-manufacture it situation so I'm learning on the go.
I dont know why it would have 5 wires
What are the wire colors and what year and transmission was the switch for?
Maybe someone can look into this deeper once they know that info?
Dave ----
Its just a solid Black wire - this is a column mount NSS for a C4 trany
All the NSSs I find that are column mount for automatics have the same 4 wires and the connector is a 4 pin like a trailer plug (3 male, 1 female on part goes with switch, 3 female and 1 male on truck harness half). Do you have a picture or part number (if new)?
Sorry - the truck connector was the 5 pin. the new NSS is only wired as 4. it could be that the previous owners mixed/match some trailer connector or something to the NSS and had it wired in. I yanked all wiring(kept connectors) out cause most were rotten/cut or otherwise damaged so i opted to go with a Kwik Wire kit since it was way less costly than Painless and they are about 40 minutes from me so if I really ran into something I'd just go up by them and solve it.
