Quote
p1= +5V
p2= vref
p3= idle switch
p4= signal ground

For MS pin 3 has no use.
Pin 4 ground is to the ms board, not chassis or engine.
Generally there should not be +12V near any sensor.


I did understand that the ground is floating on the engine and ties back to MS.

I am still confused about pins 1&4. The FSM says #1 is ground. I need to check some more with the meter.

Isn't Vref the 5v+ connection? I must be confusing some of the terms.

Frank

'89 [color:"white"]G-Raider[color:"white"] [color:"black"]Supercharged 3.0L, MegaSquirt 2, lockup A/T, 2.5" exhaust, 172k, Cibie H4s/Oscar SCs, Hella Micro DE fogs, Cobra CB, Superwinch hubs, LSD rear/Aussie Locker front, Bilsteins, Lifeline AGM, Rust-Oleum