Im 99% sure that the neutral safety switch on my truck (302, C6, Nov 79 build) is failing. Looking at the various parts Im a little confused. I have identified what I thought was the semi-circular switch on the side of the transmission, but I am beginning to wonder if that is the back-up switch only.

Can someone confirm where the neutral safety switch is and what it looks like? Im supposed to take the truck to VT for the Harpoon Brewery Octoberfest this weekend, and may not be able to go if i cant resolve this issue.

 

I went through a problem with this a while back. Mine ended up being a trouble maker. There's supposedly four wires that go to the NSS on the C6. Mine had two, which were the ones for the reverse lights. But my truck doesn't start in anything but P or N like it's supposed to. I still never figured out why I only have two out of four wires on my NSS.

Anyways, what exactly is your truck doing to make you suspect the NSS?

 

I only have 2 wires coming out of the disc as well. That and the fact that Bronco Graveyard has a plunger type switch for a 80, 3-speed, small-block are leading me to beleive the switch is elsewhere, but I at a loss as to where it is. That being said the 1980 shop manual seems to indicate that they are one in the same. If you PM me your email i can send you a scan of the pages in the manual that relate to it.

I think its the NSS since it starts just fine 80% of the time. The other 20% I can get it to start if I rock the shifter through P and N a bit.

 

Can't PM ya.

Here's my switch. You might wanna try cleaning yours up, and adjusting it. There's a pinhole in the side of the switch, and if you loosen up(Don't remove) the two bolts, you can stick something small like a sewing needle into the hole and move the switch back and forth until you feel the needle go through all the holes. I think there's three, but don't quote me on that.

 

Thats the same procedure recommended in the manual, and i plan to give it a try tomorrow. The question still remains though, since there are only 2 wires is that the B/U light switch, or the NSS, and where is the other located?

 

It is the same device. I know its crazy but that little switch will resolve the b/u light issue, starting issue, and even electrical drain issues. You guys are right on target as far as the pic IS the NSS. And yes I used a 7/16 drill bit to line up my holes then bolted it down.

 

Check the color of the wires leading to the switch. If they are red/blue, then that's the neutral safety circuit. One of the back-up wires is pink/black.

 

I called the dealership this am. They seem to have confirmed my suspicions, but I will check once I get home. On the 80-82, C6, small block trucks, the disc on the side is B/U lights only. The pictorial he was looking at showed the NSS as a plunger type switch located on the top of the transmission.

And of the 2 wires on the switch on the side of the transmission, one of them is definitely black with a pink stripe.

 

On my truck the key will only turn to the start position in P and N. This is due to a mechanical interlock in the column. When you Say… “rock the shifter” do you mean you can’t turn the key to start… or nothing happens when the key is in the start position?
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Do you have a tilt wheel?
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The switch on the side of the C6 will have 4 wires and both circuits (backup lights and NSS) but the truck side of the disconnect plug might only have 2 wires, just for the back up lights. I am not really sure of all the possible combination of wiring (NSS) and mechanical column interlocking used on the different truck years just trying to add another possible explanation.
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I also believe I looked at the NSS on my truck and I had 4 wires on each side of the NSS disconnect plug???? Not really sure if I am remembering this correctly and it is raining outside so I don’t want to crawl under it to look again.
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Good luck
Jim

 

Yes, it still has the mechanical interlock that prevents it from being shifted without the key turned. With the truck in P or N I can turn the truck on (gauges, radio, lights, etc), but when I turn the key that little bit more to start, nothing happens. If I shift through the gears once or three times then back to P it will then start.

I know the switch that everyone is referring to on the tranny. Mine only has 2 wires. I have seen other switches on Napa Online and Bronco Graveyard that are nearly identical, but you can clearly note 4 wires. JBG also shows a NSS for an 80 F150 SB that is a plunger switch, looks almost like a big door jamb switch. I have a feeling its one of those fix it till its broke ideas that Ford may have had, sorta like my slide locks that they reverted to the old style after a year or 2.

 

I wonder if you're having problems with the ignition switch/rod? Moving the shift lever could jiggle something else and temporarily fix it. Just throwin that out there as a maybe.


That was a dumb idea on Ford's part. I swapped my truck over to the top pull door locks. If you're interested in that swap send me a pm and i'll tell ya all about it.

 

Here is a photo of the Switch and the Rod.

Make sure the Rod is moving at the same time the key moving.
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