I posted this in Electrical,but this section is more populated,so I posted it here too.

I'll try to keep this short.When I got my 1980 F100,the reverse lights didn't work.I had some good new bulbs layin around,so I tried them out.They didn't work.So I gave up cause it wasn't important to me.Well fast forward to yesterday.After learning a little more about the wiring on my truck over the last few months,I set out to clean the NSS on the transmission to see if that was my problem.It was covered in grease,and after a good cleaning,I put it back on.I hopped in the truck and tested the reverse lights.The passenger side worked,but the driver's side didn't.I checked the bulb,but nothing was wrong with it.I swapped another one in just in case,but nothing.I proceeded to look for any shorts or ground problems.Nothing.I unplugged the rear harness from the main plug,and checked for voltage.It's getting plenty of voltage.I checked the reverse light socket for any damage,but there wasn't any.I then noticed that there was a clump of wires all taped together in some kind of adhesive backed black cloth.I pulled the cloth off,and found 4 wires twisted together.I don't think this is Factory,and I have a feeling that it is what's keeping my reverse light from coming on.I tried looking at my hayne's manual,but the wiring diagrams don't even list half the wires on my truck.Does anybody know of a site with good wiring diagrams?Or maybe someone has a good one at their house they can have a look at for me....Here's the wiring colors if it helps...

-Brown with pink stripe that goes to the harness connector near the gas tank.
-Solid black that also goes to the harness connector.
-Green with white stripe that goes to the reverse light socket
-Another solid black that goes to the ground on the bed.

All help is greatly appreciated.

 

Recheck the color of the tracer. Is it Pink, or is it actually white. I have a listing for Brown/White Stripe, but not for Brown/Pink.


Ground wire.

Light Green/White Stripe. Left Front turn signal indicator. (Someone could have changed the socket from a donor truck,) Replace this socket. Proper color to the reverse lights are Black/Pink stripe, or Black/Red.

Same as the other black wire above. Circut (57 BK) Ground wire.

 

The brown wire is indeed a pink stripe.The green wire is actually a dark green.On the passenger side reverse light,there is a black/pink wire,and a red/blue wire.The passenger side reverse light works however.Is there a possibility that Ford was "experimenting" with the reverse lights on my year truck?Kinda like how they changed the gauge circuit paper after July 1980?The truck was built in Dec. 79.

 

No, the back-up lamp wires (Black/Pink) have been the same color since before 1973 to at least 1988. And the NSS placement has been the same since 1978.

Both sides should be the same color at the reverse lamp sockets, (Black/Pink) with a black ground wire coming out.

Red/Lt.Blue stripe wire is the start circut that goes from the ignition switch. to the NSS on an automatic, to the starter solenoid.

There should be four wires at the NSS.

2 Red/Lt. Blue stripe wires. One going in from ignition switch, and one going out to starter solenoid.

1 Purple/Orange hash going in from the fuse panel (Back up lamp power).

1 Black/Pink stripe going out to the Back up lamps.

 

Both sides have the black/pink wire,but neither side has the black ground wire..When I look inside the socket where the wires go in,there's only a place for two wires.

There are only two wires at the NSS.

The two wires on my NSS do not match any of the wires you just mentioned.

 

If it makes any difference,even though there's only two wires going to the NSS, the truck will still not start in any gear except for Park or Neutral like it's supposed too.And some extra info,before I cleaned the NSS,the reverse lights didn't work at all.Once I thoroughly cleaned the NSS,the passenger side started to work.

 

Quote:

Originally Posted by fordtruckman80

If it makes any difference,even though there's only two wires going to the NSS, the truck will still not start in any gear except for Park or Reverse like it's supposed too.

The thing is supposed to be able to start with the tranny in reverse? Don't you
mean Neutral?

Quote:

And some extra info,before I cleaned the NSS,the reverse lights didn't work at all.Once I thoroughly cleaned the NSS,the passenger side started to work.

This makes absolutely no sense to me; are you certain you are playing with the
Neutral Safety Switch and not the Reverse lights switch?

 

Well, what do you have there?

 

Yea,I meant Neutral.Yes i'm playing with the neutral safety switch,it's bolted to the driver's side of the transmission,and then the shift linkage bolts over that.

Is there a separate backup light switch somewhere else that I don't know about?

The two colors coming off the NSS are black/red or pink(faded and can't tell),and the other is a brown with little yellow dashes on it.The NSS is the original Ford unit.

 

That's all there's supposed to be. Two wires.

One black/pink wire (some are Black/Red) (Same as at the NSS), and one Black wire (ground), at each socket. Been that way since 1978.


This is interesting, as this is atypical of the factory diagram.

Standard transmission or automatic. I assumed you have an automatic, because the Standard transmission does not use a NSS. Standard transmission uses only two wires, and is a reverse lamp switch.


On an automatic, the NSS has to have four wires to function as designed.

One set for the start circut, and one set for the Reverse lamp circut.

Start Circut: (2) Red/Lt. Blue wires. One coming from the ignition switch, and one going to the starter solenoid. The NSS interupts this circut in any gear position except Park or Neutral.

Reverse Circut: (1) Purple/Orange hash wire coming from the fuse panel. (Hot in run), and (1) Black/Pink (or red) stripe wire, going to the reverse lamps. (hot in Reverse) The NSS interupts this circut in any gear position other than Reverse.

 

It's a C6.The weird thing is,I went out and tried to start the truck in all the gears except Park and Neutral,and it wouldn't let me start it.I guess that means the NSS works.

My question is,are there supposed to be 4 wires coming out of the NSS?Cause the wires I see coming out are black/red(or pink),and a brown/hash.That kinda matches what you listed for the reverse circuit.

I looked at my starter solenoid,and there's a red/blue wire that's attached to the single small post,right by where the negative battery cable bolts to the solenoid.Is this the wire?

Also,just to be sure,the truck is a 1980.

One more question,do all the trucks come from factory with two license plate lights?Is it required by law to have two?My bumper has two cutouts,but I can only find one set of the wires...

 

Quote:

Originally Posted by fordtruckman80

One more question,do all the trucks come from factory with two license plate lights?Is it required by law to have two?My bumper has two cutouts,but I can only find one set of the wires...

AFAIK they all came with two but there is no law dictating how many there needs
to be, I think the law only states that "the rear license plate shall be visible from a
distance of X feet (at night)" and how you make that happen is up to you. At
least, this is my understanding; I could be wrong.

 

Okay,that's what I wanted to know.

 

I think you mean where the positive cable attaches to the solenoid.

1980, did that year even *have* a neutral safety switch? My 1981 F350
T18 manual trans has no such critter.

What color are the hash marks on the brown wire?

 

I spent most of my day working on the truck,so i'm a bit tired,I meant positive.

Yes,here's a pic of it in fact..




The color of the hash marks is yellow.