Brutalowner

I bought a OEM tach, minus the harness that plugs into the truck harness. Anybody have a diagram for the back of the Mopar tach? My 92's harness plug has 4 wires, orange-lights, black-key on power, black-ground, grey-signal from crank?
Thanks in advance.

BC847

-> The initial Tachometer plug and where the wires go from there (zoom in for a better view).





-> The Engine RPM signal wire from the PCM going to the plug (zoom in for a better view).





-> And the Switched +12vdc power going to the plug (zoom in for a better view).



As found in the sticky here ~ https://www.dieseltruckresource.com/...d.php?t=173561

Brutalowner

I found that sticky. I need a diagram of the back of the tach. You'd think it would be a no brainer. Am I missing the actual tach diagram in the schematics shown?

Brutalowner

Anybody got a pict of "SH40" or 48

deking1970

I've got a picture of the back of my tach in my profile, you can see it as soon as it is done with the approval thing.

deking1970

There is an R B & G next to the terminals for the red, black and grey wires
if you look at the plug on the side with the slot in it the wires are from left to right black, orange, red, grey. I hope this helps.

Brutalowner

Thanks, Deking! That's exactly what I'm looking for.

BC847

Perhaps this should be added to the sticky.

Brutalowner

I say "Sticky". I was too worried about the PCM damage to just "hook it up", having no tach-side harness. After looking at deking's pic. and reading the text, it works great. Poor truck's dash has been out since Sunday morning....
This was invaluable info, for me. Thanks guys!!