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Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 3845 PID: SPN: 5603 FMI: 31 Cruise Control Disable Command- Condition Exists

Circuit DescriptionThe adaptive cruise control system sends commands to the ECM via the J1939 data link to limit engine speed and maintain a set following distance behind a vehicle travelling more slowly than the current cruise control set speed.

Component LocationThe SAE J1939 data link wiring and the SAE J1939 devices vary by OEM options.

Conditions for Running the DiagnosticsThis diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the adaptive cruise control system was disabled for more than 30 seconds.

Action Taken When the Fault Code is ActiveThe ECM logs the fault code immediately when the diagnostic runs and fails.Conditions for Clearing the Fault CodeThe fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.

Shop TalkThis is an information fault code indicating that the adaptive cruise control system was disabled. The cruise control must be manually engaged when this condition exists.

Possible Cause:1) ECM calibration

Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 3844 PID: SPN: 5605 FMI: 31 Cruise Control Disable Command- Condition Exists
Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 3843 PID: SPN: 5603 FMI: 9 Cruise Control Disable Command- Abnormal Update Rate
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Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 3737 PID: SID 115 SPN: 1675 FMI: 31 Engine Starter Mode Overcrank Protection- Condition Exists