Faulty Additive Pump
Additive Pump harness is open or shorted
Additive Pump circuit poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
Additive Pump Open/Short to Ground is the generic description for the P1466 Audi code, but the manufacturer may have a different description for your model and year vehicle. Currently, we have no further information
about the P1466 Audi OBDII code.