MSD 5105 alternator wiring help

[msdtech1955]

3G-ALT_wiring.gif

if you look at this drawing....

ford msd

white/black s-

ltgreen/red l- charge indicator ( factory charge light)

yellow/white 1/f---field ( turns on and off with the key)

heavy blak/orange battery

p---- not used!

[hb32]

Thanks and will talk to the harness manufacture for mor info.

[msdtech1955]

any updates?

[hb32]

Awaiting a battery for installation and word from the harness manufacturer. You post states "white/black s-" what does that mean?

[msdtech1955]

s--is voltage sensing

zzzaltpinout.gif

[hb32]

Originally Posted by msdtech1955

s--is voltage sensing

Attachment 2389

I suspect that the volt sensing "S" wire from alt plug out connects to alt batt post?

Also need to confirm the wiring on the plug out of the MSD alternator.
The plug out shows 4 wires but the alternator only has 3, black, grey and red. Am I correct that the black wire is "volt sensing" or "S", the grey wire is "switched 12 volt" or "IF" and the red wire would not be required if we follow the schematic by connecting a indicator lamp or resistor in series with "switched 12 volt/"IF" grey wire?

[hb32]

When I run a 10 gage wire thru battery side of starter solenoid to the alternator, I hear a humming noise from alternator with key off. Did I do something wrong?

[hb32]

Also, is it possible that the internal regulator/rectifier is not working and is this part available as I don`t want to set a $400 paper weight on the shelf.

[hb32]

Still looking for help on this. According to all the info and schematics, the "S" Ford OEM stock white/black wire is suppose to jumper to the "S" terminal on the alternator. I don`t see one, am I missing something?

[hb32]

Originally Posted by msdtech1955

s--is voltage sensing

Attachment 2389

What does this connect to??