Cummins ISX CM870 (2003-06) Fault Code: 287 PID: P091 SPN: 19 FMI: 19 SAE J1939 Multiplexing Accelerator Pedal Sensor Error. The OEM vehicle electronic control unit (VECU) detected a fault with its accelerator pedal.

If the OEM vehicle electronic control unit detects an error with the accelerator pedal sensor, it transmits an error message to the ECM. This fault code is set active when the ECM receives an accelerator pedal sensor error message from the vehicle electronic control unit over the SAE J1939 data link.