P1939

Fuel fired heater control - circuit high

P1938

Fuel fired heater control - circuit low

P1937

Fuel fired heater control - circuit/open

P1936

Clutch switch/sensor signal

P1935

Brake switch/sensor signal

P1934

Vehicle speed signal

P1933

Fuel level signal

P1932

Fuel additive level - circuit low

P1931

Fuel additive pump control - circuit high

P1928

Fuel additive pump control - circuit/open