Voltage drop at ballast resistor

Paladin06 said

OK, I performed the steps you suggested below:

The drop to 10 volts from 12.5 even with the resistor's feed side (probably blue?, or blue with trace?) is something else. Power is going somewhere and its not the ECU or coil. See if disconnecting the alternator's field ground (green wire at the alternator) changes that reading. If not, try the field positive (probably blue?).

With the green wire disconnected I read 12.45 volts at the blue wire to the ballast resistor. :) Where do I go from here?

Click to expand...

Really does not matter "where it's going" (unless it's a short) it is still a drop. The VR power and alternator field are both supplied off the blue wire. so now backtrack from the resistor back to the battery. I already "wrote lots" on where to check above........bulkhead connector.......ignition switch.......etc......back to the battery

And again.........consider installing a relay fired by IGN1 to operate the IGN1 loads. Don't forget that drop in that circuit is what causes the VR to overcharge the battery!!