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Renxus

Well-known member
Joined
Jul 27, 2022
Messages
52
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Location
Estonia
My Car
Ford Mustang 73 Convertible 351C
Ford Mustang 70 Fastback 302
Good day,

Sorting out the wires of my 73 convertible. Some wires and things are idle but I am curious what was the purpose?
I just swapped the alternator to a modern one-wire and some things are leftovers.
1. What box is this? It is connected to the solenoid BAT post.
2. The leftovers - are any of them important? Leftovers from the voltage regulator that is not needed anymore.
3. Some old connectors close to the firewall near the power break. Only four-pin powers up. Got my 12V RUN line to the new distributor from it.

Regards,
Rene
 

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Picture 3 looks like the connections for the transmission and the engine feed.

Round white one I believe goes to the light in the pointer in the floor shifter.

Square blue one goes to the transmission neutral safety switch and backup light switch, along with another black square connector. I think maybe that blue one plays a role in the seatbelt warning system.

The flat 3 and 4 conductor ones go to the harness that lays on top of the engine along the driver's site of the intake. It has the hookups for the oil pressure sender, water temp sender, coil, throttle position solenoid, AC compressor, coil+, and a couple other ones.
 
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Thanks all. Seems like the breaker for the top and the alternator lamp wires will stay in business. All other things seem to work without the rest.
Building step by step. Now trying to figure out why my Edelbrock vacuum tries to kill the new Perform HEI distributor. Not bored at all :)
 
Back again with my sockets. Not much help with the old diagrams or am I just impatient :)
They are not needed for now but just out of curiocity I'd like to know what they are needed for? Perhaps someone has a clue? I have no place to plug them but I rahther leave them hanging (hopefully one is for AC that is cut out now but perhaps one day I would reinstall one). The neutral switch and wiper motor are covered already.
P_20240223_081341.jpg
 
From left to right: 4 pin plug is engine gauge feed; emissions control plus AC; PRNDL lamp; seat belt; brake proportioning valve. You're missing a 4 pin square NSS/BU plug.
Thanks Midlife!
However, can you educate me a bit more?
1. Engine gauge - where it supposed to connect and show what and where?
2. Emissions control - how this works and where was it connected?
3. PRNDL (PRND12 in my case) lamp - the illumination of it? I got it wired straight with dash bulbs, it is a wierd place for this socket here :)
4. Seat belt (warning lamp?) - again wierd place to have it in the engine bay. Where should it connect here?
5. Brake proportioning valve (failure indicator?) - the line goes to the break light in dash and shows a failure in the valve? Or does it something else? Seems I have a round socket with one wire on the valve itself.

NSS/BU plug is missing indeed and these are connected directly by the previous owner. No trouble there.
 
1. It's the coil, oil, water temperature, and anti-stall carb valve.
2. Don't really know...it's usually packaged with the engine gauge feed harness.
3. I believe the wire connects to this and plugs into the shifter console from the underside.
4. It's part of the NSS/BU harness for that year.
5. Yes, show's failure in valve and plugs into the proportioning valve in the engine compartment.
 
Hi Rene,
I am not sure where I got this wiring diagram. Someone spent a lot of time creating or finding the co0nnector drawings. hope it helps.
 

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To add to Midlife's reply....

1 - the engine gauge harness covers plugs 1 and 2, see annotated image below.
2 - It was part of the EGR system, dig into the wiring diagrams that Spar_ky posted.
3 - the shifter light wiring runs through the tunnel, that's just how Ford did it.
4 - seat belt warning switch was integrated into the neutral safety switch. see second pic below. FMX would be mounted in the shifter.



1708876775720.png

C4 / C6 neutral safety switch

1708877349227.png
 
To add to Midlife's reply....

1 - the engine gauge harness covers plugs 1 and 2, see annotated image below.
2 - It was part of the EGR system, dig into the wiring diagrams that Spar_ky posted.
3 - the shifter light wiring runs through the tunnel, that's just how Ford did it.
4 - seat belt warning switch was integrated into the neutral safety switch. see second pic below. FMX would be mounted in the shifter.



View attachment 86044

C4 / C6 neutral safety switch

View attachment 86045
Thank you! Smarter again. I just leave them hanging for the historic purposes; all needed seems to be covered. Building a relay block now and it should all come out good with better headlights and electric radiator vents.
 

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