Circuit Description
Fuel pump self-test is provided at power-up. In an ideal case, an active Fault Code 374
indicates a fuel pump defect and can trigger the engine light/malfunction indicator light at key on.
Component Location
The fuel pump is located on the backside of the gear housing. Refer to Procedure 100-002 in
Section E for detailed component location.
Shop Talk
If Fault Code 374 becomes active while the engine is operating, it can possibly be due to a
power glitch or to voltage spikes. Check the power supply circuit for loose or shorted wires and/or fuses. Inspect the power supply relay.
Cummins ISB CM550 (1990-94) Fault Code: 373 PID: SID 233 SPN: 1077 FMI: 3 Fuel Pump Fuel Shut Off Error
Cummins ISB CM550 (1990-94) Fault Code: 373 PID: 232 SPN: 1077 FMI: 3 Fuel Pump Fuel Shut Off Error
Cummins ISB CM550 (1990-94) Fault Code: 372 PID: SID 233 SPN: 1077 FMI: 11 Idle Select High/Low
Cummins ISB CM550 (1990-94) Fault Code: 372 PID: 1283 SPN: 1077 FMI: 11 Idle Select High/Low
Cummins ISB CM550 (1990-94) Fault Code: 369 PID: 1690 SPN: 1078 FMI: 2 Fuel Pump To Engine Synchronization Pulse Not Recognized
Cummins ISB CM550 (1990-94) Fault Code: 368 PID: SID 254 SPN: 1078 FMI: 8 Fuel Pump Can Not Reach Commanded Timing
