Neutral Safety Switch

[mudbilly]

I needed a new Neutral safety switch and not learning from a million previous mistakes, didn't bother to see what the plug(s) looked like on the end before buying a new one.

I get it yesterday and went to install it today. Easy to remove the old switch, but it has 2 plugs on it and the new one only has 1 plug. Looking at different versions online I can find one with 2 plugs, but it appears that they only have 2 wires per plug. I assume 2 for the safety circuit & 2 for the revers lights. My switch has a 4 wire plug and a 2 wire plug. :chin:

Can any one shed any light on this conundrum ? 

I did take the switch apart just to learn what it looked like inside.

 

[rackerm]

There are two different switches.

C9ZZ-7A247-B is a single four plug Neutral Safety Switch for a C4 or C6 is the same for cars built after 12/15/1966-1969

D2ZP-7A247-AA, BA or D2ZZ-7A247-C Neutral Safety Switch has a two plug and a four plug and is for Mustangs/Cougars produced AFTER December 1, 1971

 

[midlife]

The four pin plug is your standard NSS/BU switch; the blue 2 pin plug is for the seat belt reminder system.

 

[mudbilly]

The four pin plug is your standard NSS/BU switch; the blue 2 pin plug is for the seat belt reminder system.

Thanks

Cool, since I don't have the seat belt reminder functioning, I can just use the new switch. ::thumb::

How does the seat belt circuit work ? Reminder light on when you shift into gear and then off when you latch the seat belt ?

 

[rackerm]

The four pin plug is your standard NSS/BU switch; the blue 2 pin plug is for the seat belt reminder system.

Thanks

Cool, since I don't have the seat belt reminder functioning, I can just use the new switch. ::thumb::

How does the seat belt circuit work ? Reminder light on when you shift into gear and then off when you latch the seat belt ?

Yes. It completes a ground connection thru the seatbelt retractors. There is also passenger seat sensor under the seat that triggers the reminder when the passenger seat has weight on it when in gear, and don't forget there is a relay buzzer as well.

 

[Ryunker]

I needed a new Neutral safety switch and not learning from a million previous mistakes, didn't bother to see what the plug(s) looked like on the end before buying a new one.

I get it yesterday and went to install it today. Easy to remove the old switch, but it has 2 plugs on it and the new one only has 1 plug. Looking at different versions online I can find one with 2 plugs, but it appears that they only have 2 wires per plug. I assume 2 for the safety circuit & 2 for the revers lights. My switch has a 4 wire plug and a 2 wire plug. :chin:

Can any one shed any light on this conundrum ? 

I did take the switch apart just to learn what it looked like inside.

Can you post a photo of the other side of the switch apart? Going to attempt a repair of mine for reverse lights, and want to see what I am in for

 

[mudbilly]

It was relatively easy to take apart. I had to drill out these 2 swages and used a tiny flat screw driver to pry up the Circuit Board. The copper rods that look like fuses are spring loaded and makes the connection between the wire harness and the switch location.

You'd have to drill and tap these in order to put it back together again.

Here is the opposite side. Really nothing there, this is the side you see when locking at the transmission.

Drilled out an pried open

Close up of drilled pad.

Circuit Board inside, you can see the copper strip that makes the connection. There was a flat precut gasket all around the border but that pretty much fell apart when I opened it up.

I'm thinking that if I'd clean these pads that the connections would work again, But that is just a guess, I didn't try to see if there was copper underneath. I'll check hese out later today when I get back out to the garage.

The inside is full of grease.

 

[mudbilly]

Got the new switch in and it works as it should. Start in Park & Neutral, no go in gears.  Of course I only tried it a couple times, as long as it doesn't let me stranded somewhere.

But I still do not have back up lights.

 

[rackerm]

Got the new switch in and it works as it should. Start in Park & Neutral, no go in gears.  Of course I only tried it a couple times, as long as it doesn't let me stranded somewhere.

But I still do not have back up lights.

Did you adjust/Calabrate the NSS using a pin in the hole? I can post the full procedure if needed.

 

[SteveO_71]

It might be good to have the adjustment procedure added as part of all the documentation in this post. Then someone can just bookmark this post and have it all in one spot.

 

[rackerm]

It might be good to have the adjustment procedure added as part of all the documentation in this post. Then someone can just bookmark this post and have it all in one spot.

A PDF from the 1973 Shop Manual is already posted on the site... https://www.7173mustangs.com/thread-c6-transmission-linkage-questions?page=2&highlight=neutral+saftey

Here it is again.....

Shop Manual Volume 1 - Part 17-02 Shift Control Linkage.pdf

 

[mudbilly]

Did you adjust/Calabrate the NSS using a pin in the hole? I can post the full procedure if needed.

Yea, I even found a # 43 drill bit to make sure. I figure it is not an adjustment in the switch, since it works as it is supposed to as far as starting goes.

Got this from Stangnet

----------------------------------------------

Ready? straight from the factory manual

1 Remove the trans linkage rod from the tranmission downshift lever

2 Remove the transmission downshift outer lever retaining nut and the lever.

3 Remove the two retaining bolts

4 Disconnect the two electrical connections, then remove the switch.

5 Install new switch with the bolts

6 With the transmission manual lever in neutral, rotate the switch and install a #43 drill bit into the gauge pin hole. The bit should go in the switch 31/64 in order to make sure the adjustment is correctly made. I wrapped the drill with tape when I did mine, made it easy to know how far it was in.

7 Tighten the attaching bolts and remove the drill

8 Install outer downshift lever and attaching nut. Install the downshift linkage rod to the downshift lever. Note on some years the rod may be a cable.

 

[Don C]

With the transmission in reverse, check the continuity beteen the two backup light terminals. If the reading is close to 0.0 ohms the switch is OK, if not, the switch is bad. As has been stated on here many times, new does not mean good.

 

[midlife]

As has been stated on here many times, new does not mean good.

:bravo: I believe that the older one gets, the better one gets as well! 

Oh...you're talking about car parts, eh?  Nevermind...

 

[mudbilly]

With the transmission in reverse, check the continuity beteen the two backup light terminals.

Which color wires from the switch should I check continuity for when in R ?  I assume the other 2 must drive the starter circuit ?

 

[midlife]

With the transmission in reverse, check the continuity beteen the two backup light terminals.

Which color wires from the switch should I check continuity for when in R ?  I assume the other 2 must drive the starter circuit ?

There should be a black/red and a white/purple wire.

 

[mudbilly]

There was continuity across the white/purple & black red when I put the shifter in R, so the switch was good, (thankfully)

But I didn't have power to the White/Purple feeding into the connector with the key on. Although I could get the backups to light by putting 12v to the black/pink on that side of the connector.

Didn't want to go chasing wires, and since I have been running wires all over the engine bay, I was able to easily tap into a switched 12v that I had run for my headlight running lights. Spliced that to the connector white/purple going into the switch and Voila, I can finally see what is behind me when I back up at night. ::thumb::

:thankyouyellow:  ALL

 

[midlife]

There was continuity across the white/purple & black red when I put the shifter in R, so the switch was good, (thankfully)

But I didn't have power to the White/Purple feeding into the connector with the key on. Although I could get the backups to light by putting 12v to the black/pink on that side of the connector.

Didn't want to go chasing wires, and since I have been running wires all over the engine bay, I was able to easily tap into a switched 12v that I had run for my headlight running lights. Spliced that to the connector white/purple going into the switch and Voila, I can finally see what is behind me when I back up at night. ::thumb::

:thankyouyellow:  ALL

Power for that white/purple wire comes from the fuse box, top left.  It also powers the factory radio plug and turn signal flasher can.  I wonder if your turn signals don't work...if not, then the fuse is likely the suspect.  If they do, then something is catty-whompus* with the white/purple wire running through the underdash harness and the headlight harness.

*A highly technical electrical term

 

[mudbilly]

Midlife, you would slap me silly if you ever got to see what I have done to the wiring in my car. When something doesn't work, or i want to add something, I just bully my way through it and run new wires.

I have always hot and switched hot wires running everywhere. I can pretty much get power anywhere I want it. It is fugly under and behind the dash. But the turn signals, emergency, and I think everything else now works. I think the reverse lamps were the last hurdle.

Have multimeter will travel. :wrench: