Ford P1643 OBD-II Trouble Code Definition: P1643 Engine Speed Output Circuit P1643 Ford OBD-II Trouble CodeDescription: OBD Trouble Code P1643 Engine Speed Output Circuit Sorry no other information,Please help us to improve,Any information is appreciated.Thanks. PSA OBD Trouble Code P1643 Fuel pump monitor circuit Low input Sorry no other information,Please help us to improve,Any information is […]