73 Mach I Neutral Safety Switch

Need info on finding it , testing and adjustment. My Mach has a FMX trans

 

[Hemikiller]

FMX has the NSS in the shifter body. Remove the shifter bezel and you can perform any needed adjustments.

 

[mrgmhale]

Need info on finding it , testing and adjustment. My Mach has a FMX trans

Do you need schematics for Circuit 32 that goes through the NSS and then to the Starter Relay?? If so, just replay in this thread or email me at [email protected].

 

[mrgmhale]

As aside, the NSS for 1973 is a little different than the NSS for 71-72 (and earlier) switches. For 1973 the NSS is a combination switch. Two wires are for Circuit 32 (32A), two are for the Backup Lights, and the 3rd pair are for the defunct Seatbelt Interlock. The Seatbelt Interlock scheme was largely disabled/bypassed by nearly all of those cars initially afflicted with that horrible mess. All you need are the Circuit 32 wires, and the wires for the Backup Lights. If you can;t find 1973 specific 6 wire NSS switch, a 71-72 will work fine, as the Interlock Plug is separate from the NSS and BUL plug

 

[Mach I Pony]

OK stupid question time. How do you ask/request help here ? I must have been daydreaming when they covered the section. Funny thing I've done it before just forgot how.

Trying to locate the constant voltage regulator for the dash lights
73 Mach1

 

[cv_72mustang]

Believe it's on the instrument cluster flex circuit board. It's a 'bimetal' old school regulator. You can post on electrical , lighting forum. Also do a search. I'm sure there been a number of posts on this.

Thread 'Dash printed circuit' https://7173mustangs.com/threads/dash-printed-circuit.42634/

 

[rackerm]

Here is where you will find it..

 

[Mach I Pony]

First thank you for the information.
I’m having trouble with my dash lights being extremely dim, ever when the dimmer is at its highest setting. Any suggestions?

 

[midlife]

First thank you for the information.
I’m having trouble with my dash lights being extremely dim, ever when the dimmer is at its highest setting. Any suggestions?

Yes. My advice is to lose about 30-40 years of age. Oh, to be young again and to be able to see things!

 

[Mach I Pony]

Or I could just drive by candlelight it would be brighter, hmmmm what an enlightening solution

 

[Retired2014]

Or I could just drive by candlelight it would be brighter, hmmmm what an enlightening solution

Your dim dash lights are common to the 71-3 mustangs (although Midlife makes a valid point). Searching the “dim dash lights” topic on this site will educate you as to how to correct your problem. It has been covered several times, with several well executed methods.

 

[RIBS]

Dim dash lights can be fixed by a new headlight switch, a new voltage regulator, or by replacing lights with LEDs. I did all 3 it was the LEDs that worked for me. Read up, there’s tests to do to determine the correct path…

 

[Hemikiller]

First thank you for the information.
I’m having trouble with my dash lights being extremely dim, ever when the dimmer is at its highest setting. Any suggestions?

There are multiple reasons for dim dash lights....

1 - the bulbs get dim as they age due to deposits on the interior of the globes.
2 - the diffusers overheat and turn brown from the heat
3 - the contacts on the resistor in the headlamp switch get dirty
4 - the gloss plastic the housings are molded from from turns brown with age

Simple low-buck solution that retains the dimming ability of an incandescent lamp, is to disassemble, clean and repaint the interior of the gauge housings in gloss white paint. Replace any melted diffusers with new or good used. Clean the contacts of the rheostat on the headlight switch, the bulb housings and the terminals on the cluster connectors.

Replacement diffusers:

https://www.npdlink.com/product/lig...=10b870&top_parent=200001&year=1971&year=1971
A couple 10 packs of #194 bulbs will be needed

https://www.rockauto.com/en/partsearch/?partnum=194
FWIW, the instrument voltage regulator on the cluster has nothing to do with the dash lighting, it is only to supply voltage for the gauges.