Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 3555 PID: SPN: 1081 FMI: 9/9 Engine Wait to Start Lamp – Abnormal Update Rate

Lamp:
Amber

Reason:
A loss of communication has been detected.

Effect:
None on performance.

Circuit Description:
Normally, switches, accelerators, and other components are connected to the Engine Control Module (ECM) directly through individual wires. Multiplexing allows those same components to be hard wired to an Original Equipment Manufacturer (OEM) Vehicle Electronic Control Unit (VECU) or transmission Electronic Control Unit (ECU) in the cab. Then component values and states from components such as sensors, accelerators, and switches can be transmitted from the OEM VECU to the OEM ECM over the SAE J1939 data link.

Component Location:
The SAE J1939 data link wiring and the SAE J1939 devices vary by OEM options.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected a loss of communication with the engine wait to start lamp.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber check engine lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1. To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2. The fault code status displayed by the diagnostic tool will change to inactive immediately after the diagnostic runs and passes.
3. The ECM will turn off the amber check engine lamp immediately after the diagnostic runs and passes.
4. For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5. The reset all faults command in the diagnostic tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
Possible causes of this fault code include:
1. Incorrect terminating resistance of the SAE J1939 datalink circuit.
2. Incorrect feature and parameter settings.
3. A malfunctioning SAE J1939 datalink circuit.