1989 Neutral Safety Switch 8 pin plug / 6 pins ?

[Brnko Onr]

My NSS has failed on my 1989 5.9L / C6 / manual linkage transfer. I ordered a new one from Dennis Carpenter so I would receive the proper part, The new part showed up as a 4 wire 4 pin plug NSS. My truck has an 8 Pin oval plug with using only 6 pins (six wires) in it. Nothing on the truck has been replaced or modified, I purchased this truck in the early summer of 1989 new. I have searched high and low and cannot find a NSS with the proper plug or wiring. My questions are;
#1 Does anyone know what the extra wires go to in the harness?
I figure 1 wire is power in for Park/ neutral / start and 1 wire out for the same. Also 2 wires for the backup light circuit.
#2 Does anyone know what color each of the wires are?
I know that red/ Lt Blue is my power supply to and from the NSS but no clue of the other 4
# 3 Where I can get the proper NSS and/or possibly a part number?
# 4 Where I can find a schematic of my truck with accurate harness wire count and color for the NSS?
Any and all replies will be much appreciated.

 

[L\Bronco]

Hey Brnco
Welcome to the zone!
Can you post a pict of the nss on the trans for reference?
Im not near my computer at the moment, and a quick search only shows the 4 pin types for a C-6.
Hopefully we can get to the bottom of it.
Cheers!

 

[Brnko Onr]

Thanks for your speedy response,
Here are a couple of pics. The picture of the one with female end ( middle pic.)is the one on the NSS. The one of the male end ( trucks wiring harness) shows that it is only using 6 pins of the 8 pin plug. I also posted this pic because when I removed some of the factory tape ( it was oil saturated and coming loose) I found the area on the black wire stripped and the other wire end stripped. It does not look like the two wires were ever connected together though. Once again I purchased this bronco new in 1989 so I know its entire history and I know for sure that no one ever messed with wiring for the trans. Since my last posting I have ordered another electrical repair manual I hope that will have a more accurate schematic of the wiring system. Any help is much appreciated. Thanks Again, Rich

 

[L\Bronco]

Hey Brnko
There is lots of info out there, if you have a man t/case it uses the 4 pin version. The 6wire one is for an electronic shift t/case.
The part number you need is NS-92 For a “standard motor products” part.
Some guys are cutting off the plug and wiring it to the 4 wire version. The colours for the neutral start and b/u lamp circuits are supposed to match.
The other 2 wires are for a safety circuit in the electronic t/case.
hope that helps.
Cheers

 

[Brnko Onr]

Thanks Again for the Information and reply.
I just ordered the part from Rock Auto. The problem I have had all along is whenever I entered in the engine, transmission and manual transfer case it would only give me the 4 pin plug option. Whenever I did an online search it never brought up a 6 wire configuration for a C6 trans. I didn't want to cut and splice any of the wiring on the truck unless I had no other options. Here's A picture of my bronco, I purchased it new, Lifted with 50 miles on it, It has been garbage kept since new ands less then 62k miles on it as of today. Thanks again for all that you help, Rich

 

[L\Bronco]

Happy to help Rich.
That is a beautiful truck. I love the stance! It looks mean!
Heres mine. (I have a build thread in here on it)
“79 bronco 03 Lightning swap”
Happy holidays
Cheers

 

[Brnko Onr]

Good Morning,
Great looking truck you got there, must have all kinds of power now compared to the 351m engines of yesteryear.
I always loved the looks of the front end of the 1979's along with the fact that it was the last year of the monobeam axle. I'll have to look up your build threads on your truck when I get some extra time to relax and read. I'm getting ready to give the truck to my son for him and my grandsons to enjoy. I made a promise to him many years ago about the truck and now it's time to fulfill my end of the deal. That's why i'm combing through the truck and fixing a few odds and ends. Before turning over the truck to him we ( myself, my son and my oldest grandson ) are going to do a differential swap and four link both the front and rear of the truck. I bought a set of diner axles 15 years ago from a wrecked 2002 F250 diesel pickup ( a set of Sterling 8 lug axles) 4.10 gears with lockers both front and rear. When we get started I will have to post the project here. Well enjoyed the chat, Keep warm up there and take good care of your 79, they are getting rarer every day. Rich

 

[L\Bronco]

Sounds like an awesome project! Enjoy the build.
I built mine with a lot of help from my 3 sons, it took most of a year (off and on) the truck is amazing! We got rid of all the bad stuff in a 79. But, the memories are worth more to me than the truck. (My boys bought me the project as a gift)
Make sure you post some picts of the build!
Cheers

 

[Brnko Onr]

Good Morning L/Bronco,
Just wanted to update you on the NSS, I ordered it form Rock Auto, it arrived yesterday and it is the correct plug for my truck. ( I probably won't get around to installing it until after the weekend. Thanks for all your help, I'm still a little confused as to why my truck has a 8 pin 6 wire plug with a manual linkage transfer case. Do you think it could be that my truck was built so close to the factory changeover to the 1990 models? Didn't Ford go exclusively to Electric shift on the 1990's and newer? Well thanks again and hope you have been enjoying the holidays.
Brnko Onr

 

[L\Bronco]

Thats probably it, Ford was famous for installing 1 harness regardless of options back then, not so any more.
Happy New Year
c
Cheers!!

 

[johnnyreb]

You might want to check the BACK-SIDE OF THE PLUG IN. On my 78 their was one wire broke of--nut still LOOKED like it was all the wan down. Nice looking Bronco.

 

[Brnko Onr]

Good Morning to All,
I figured I would give you an update on the Neutral Safety switch saga. I Installed the NSS in the truck yesterday, got ready to plug it in to the wiring harness on the truck and realized I had two identical plugs. Both plugs were the male end (female pins) . I Removed the new NSS Cut the plug off the old NSS and installed a Weather proof plug in the new switches harness instead of splicing the wires on it.( luckily the wires on both the old and new switch were the same colors ) I Reinstalled it and everything is working as it should. Once again I believe it is due to very late build date on my 1989 model and Ford using up both old and new harnesses, parts and pieces. Here's a couple of pics of the plug I installed on the NSS instead of just splicing the wires. Thanks again to all for your help and interest .