5 documented codes across 23 real diagnostics.
Battery voltage, alternator and supply rails. Low system voltage cascades: P0562 arrives with a fistful of U-codes because starved modules stop answering.
Ranked by how often we actually see them
- P0562, System voltage low
- P0560, System voltage
- P0621, Generator lamp or L terminal control circuit
- P0627, Fuel pump A control circuit open
- P2500, Generator lamp or L terminal circuit low