what all does the ecm control?1992 d350 5 speed

 

The PCM controls the alternator charging, the A/C cycling, the OD shifting and the speedometer to name a few.

 

If I add a external voltage regulator will that kill the power to the ecm?Is it likely that just the voltage regulator is out and the rest is ok? thanks everybody

 

You said the A/C compressor isn't engaging, so you'll have wire that up as well.

The PCM gets power from a different wire. As long as the bulb check happens when you turn the key on (WIF and WTS lights come on for a few seconds) the PCM is marinally operational.

 

Where is the Crank sensor located on a 98 12 Valver ?

Anyone have pics ??

 

Stand in front of the truck directly in front of the fan and look down. The sensor is a little to the left of centerline on top of the crank damper.