I have a 1972 Ford Mustang, 351C-4V, 4-Speed manual with a Hurst shifter. There are two wires that connect into the manual transmission
- purple and light green. I can't find these wires anywhere in the wiring diagram. Anyone have any idea what these are? The reverse sensing switch is on the shifter, so its not that.
Some 70's cars had a transmission switch to change spark advance in high gear. (Some were third and high.) You can remove the connector and check it with an Ohmmeter.
Al
If you don't get it figured out, give Dan Williams Toploader Transmissions a call. He can answer all your questions.
Look at 705-2 in the wiring diagram. I have them on my 1972 and I'm pretty sure they're for the seatbelt light. The circuit should be open in neutral and closed in any gear. The timing circuit referenced earlier is a brown wire.
So you're saying that the seatbelt light would only go on if the car is in gear? Interesting. I'll look into that.
Yes 72 and 73 have sensors in the seat belt retractors and a switch under the passenger seat. The transmission energizes the circuit with the light and buzzer. If the seat belts aren't extended and the car's in gear, the light and buzzer go off. 73 went one step further with a starter interlock.
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