Mystery wire………

[doghead]

Pics 5 and 6 is what my truck looks like.

So my truck must have a physical interlock happening while in gear(keeping the key from turning to the start position).

Dstang, can you try turning your key to start, with it in gear, and tell me if the key refuses to turn or if it does turn.

 

[FMJ]

Nope, no go. The switch (back up light switch), already has a plug to it. Two blue and one green wires.

Um, does your neutral safety switch have wires connected to it?

 

[FMJ]

The pic I posted is from a retailer and it was found searching the part number(22514861) in the -20P. Standard Motor Products NS41 - Standard Motor Neutral and Backup Safety Switches - Overview - SummitRacing.com notice they call it a neutral saftey switch and reverse light switch!

My switch in my truck, does NOT look like that switch(exactly). Mine appears to have a white "cap" over the area where the 2 copper looking terminals are in the pic I posted).

I did not find any mention of a neutral safety switch listed in the tech manuals.

My truck, the key will not physically go to the start position, if you try to start it in any position other than P or N.

Again, I can not find that plug with those 2 wires on my truck(1986 M100

I do not have a civilian truck to look at to compare.


While it is a bit of a safety concern, I would live with it for now, until we get an answer(why you have that plug in a CUCV).

I am wondering if your truck(early production) used a civilian harness that may have been adapted for the CUCV line.

Does anyone else have an early(1983 build date) CUCV, and can tell us if they have that wire/plug ? And, can you start early CUCVs in any gear?

I've got an 83 1008 at home (NM) I'll look at it this Wed. and report.

 

[dstang97]

OK i guess i was right when i said earlier that the 83 might have a different wiring harness. It is in fact a neutral safety switch. I first un-pluged it and it would not start in any gear. Hooked it pack up and it worked. It has nothing to do with the backup lights because nothing was affected. One weird thing i did notice is that i can only start my truck in park. I always thought you could in neutral also.

 

[doghead]

It does 2 things,neutral and backup lights. The 2 copper colored terminals(pic I posted) are for neutral, the other 2 terminals along the top of the switch, are for the back up light.

It is adjustable(position). I had to adjust mine, to get the back up lights on, when in reverse.

 

[dstang97]

It does 2 things,neutral and backup lights. The 2 copper colored terminals(pic I posted) are for neutral, the other 2 terminals along the top of the switch, are for the back up light.

It is adjustable(position). I had to adjust mine, to get the back up lights on, when in reverse.

I ment the yellow and purple wires. Not the switch itself.

 

[doghead]

Well, in post # 21, I posted a pic of a civilian wiring schematic. I didn't look it over completely but I would guess those wires interrupted the 12v starter solenoid, when in not in P or N. If(speculation) they used a civy harness, maybe they simply diverted the start position (purple with white tracer) wire, over to the under-dash relay(directly from a military only column harness). Just a guess.

 

[dstang97]

Makes sense purple with white tracer.

 

[doghead]

One other thing(different than civilian) that I have never looked to see why is, the fact that the signal lights work without the key on.

 

[FMJ]

One other thing(different than civilian) that I have never looked to see why is, the fact that the signal lights work without the key on.

I noticed that too. . . .

 

[dstang97]

I asked that question a long time ago. Someone told me its the way how they did the wiring. As you probably know civi's steering columns are a direct replacement

 

[73m819]

I guess, if everything works with it unplugged, them leave it alone!

Could be the "in 10 sec. SELF DESTRUCT wire upon connection"

You dissapointed me with your reply, Ron.

I thought for sure, you'd post it was the wheel-chock tether...

I thought about that when I read post#1, but since I am a KINDER-GENTLER person today, KNOWING how some get there feelings hurt VERY easy, I decided to lean to the SAFTY comment

EDIT, If I feel the KINDER-GENTLER wareing off. I might have to come back an EDIt

EDIT
Well I feel the KINDER-GENTLER person that I was this morning has left the building along with ELVIS, The reason I mentioned the "in 10 sec. SELF DESTRUCT wire upon connection" is I did not want someone hurt from flying wheel chock peices, it always pays to be SAFE

 

[joediveguy]

Um, does your neutral safety switch have wires connected to it?

Yes, one plug with two blue wires and one green wire going into the switch.

 

[FMJ]

Yes, one plug with two blue wires and one green wire going into the switch.

Well the point I'm trying to make is, your neutral safety switch is not working, most likely caused by the connector in your pics not being connected.

 

[joediveguy]

as requested.

Thanks for the pic’s! I am a visual person and that is just what I needed!

So, if I am looking at pic #2 & #3 correctly, there are two connections, one for the Yellow & Purple with a white stripe to plug into AND one for the two blue wires and one green wire to plug into. Holy crap it has been a long day!

I’ll pull the plug tomorrow and take a look at it. I got destracted today trying to fix the Parking break and bleed the breaks. Turns out the PO replaced the left rear cable with the wrong one that is too short and had a nipple, tee hee, which was too big so it kept breaking the connector. AANNDD, the master cylinder was gummed up with dot 3. Long story short, looks like I will probably be replacing both rear wheel cylinders and break lines!

Thank you guys for all your help and wonderful insight. I’ll keep an eye out for the flying wheel chock pieces! Cheers

 

[joediveguy]

Well the point I'm trying to make is, your neutral safety switch is not working, most likely caused by the connector in your pics not being connected.

Exactamundo! Thanks for your help. I need a drink!

 

[doghead]

Wow, you needed more coffee in the begining, now you need a drink(spirits?)!

 

[joediveguy]

Wow, you needed more coffee in the begining, now you need a drink(spirits?)!

Yes, of the “spirit” kind. Frustrating day, I hate working on something some other idiot has screwed up. At least I am not covered in rust. This truck has a real solid frame. I am used to working on old mustangs where every nut you twist is rusted up! The underside of this guy was nicely preserved by the automatic undercoating system from the trans pan! You all have a good night!

 

[hilber]

Yes, of the “spirit” kind. Frustrating day, I hate working on something some other idiot has screwed up. At least I am not covered in rust. This truck has a real solid frame. I am used to working on old mustangs where every nut you twist is rusted up! The underside of this guy was nicely preserved by the automatic undercoating system from the trans pan! You all have a good night!

That undercoating does work well.

 

[top_prop]

One other thing(different than civilian) that I have never looked to see why is, the fact that the signal lights work without the key on.

I just trouble shot a few electric things today... lost all lighting and had already bypassed the tactical lighting/black out switch... so I poured over the electrical diagrams.

I think the simple answer is by passing the power for the head lights first through through the tactical lighting/black out switch then feeding it to the turn signal fuse they only needed one simple switch to interrupt both systems, but the signals would work with the key off. Otherwise the tactical lighting/black out switch would need more poles to do the same function and would cost more and be larger.

Engineers are pressed to save pennies everywhere they can get away with it. It frustrated my dad (an experimental vehicle builder at GM) for his entire career.