About two nights ago the battery light came on in my truck (2014 2500 cummins).
The voltage read-out on the dash was 11v. The RaceME tuner was reading 0.98v.
Made it home, and the next morning I checked the DTC's in the RaceME, and it had P063C: Generator Voltage Sense Low, P063D: Generator Voltage Sense High, and P065A: Generator System Performance.
I hooked up the battery tester, and it read 12v on both batteries, but wouldn't read a load test or the alternator (said battery charge too low).
The volt meter was reading 11.5v and 3.6v ripple.
Sooo, I'm assuming it's an alternator issue, because I assumed the voltage regulator was internal to the alternator on this truck.
Replaced the alternator this morning and checked the RaceME and it was reading 13.5-14.5v.
Put everything back together, and checked the RaceME again, and it was reading 0.73v!
After reading a few other posts I found that the voltage regulator is actually part of the PCM, now my question is, is my tuner programming screwing with the voltage readings?
I wiped the ECM tuning back to stock, and no change, then re-loaded the custom tunes, still reading low voltage.