This fault can occur when the ECM is set up properly (components enabled and OEM VECU source addressed correctly) to receive information from an OEM VECU, but the OEM VECU is actually transmitting a message that says that component is not available for multiplexing.
1)Check OEM multiplex settings.
Cummins ISX CM870 (2003-06) Fault Code: 285 PID: S231 SPN: 639 FMI: 9/9 The ECM expected information from a multiplexed device but did not receive it soon enough or did not receive it at all.
Cummins ISX CM870 (2003-06) Fault Code: 284 PID: S221 SPN: 1043 FMI: 4/4 Engine Speed Sensor Supply Voltage Circuit – shorted low. Incorrect voltage detected on the ECM voltage supply line to the engine speed sensor.
Cummins ISX CM870 (2003-06) Fault Code: 265 PID: P174 SPN: 174 FMI: 4/4 Engine Fuel Temperature Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at engine fuel temperature circuit.
Cummins ISX CM870 (2003-06) Fault Code: 263 PID: P174 SPN: 174 FMI: 3/3 Engine Fuel Temperature Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at engine fuel temperature circuit.
Cummins ISX CM870 (2003-06) Fault Code: 259 PID: S017 SPN: 632 FMI: 7/7 The ECM detected that the fuel shutoff valve is stuck open mechanically or leaking.
Cummins ISX CM870 (2003-06) Fault Code: 256 PID: P171 SPN: 171 FMI: 4/4 Ambient Air Temperature Sensor 1 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at ambient air temperature circuit.