Cummins ISB6.7 CM2350 (2013-17) Fault Code: 1777 PID: SID 15 SPN: 2634 FMI: 4 Power Relay Driver Circuit- Voltage Below Normal or Shorted to Low Source

Cummins ISB6.7 CM2350 (2013-17) Fault Code: 1777 PID: SID 15 SPN: 2634 FMI: 4 Power Relay Driver Circuit- Voltage Below Normal or Shorted to Low Source

Circuit Description
The Power Relay provides voltage to the smart power sensors at key on. The Engine Control Module (ECM) controls the relay that switches on power to the Aftertreatment Temperature sensor modules, ammonia sensor, inlet and outlet NOx sensors.

Component Location
The power relay is located in the engine harness near the Engine Control Module.

Conditions for Running the Diagnostics
This diagnosic runs at key OFF when the relay is commanded OFF.

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the power relay signal voltage was low for a calibrated period of time.

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, key OFF for 1 minute, then key ON for 1 minute.
2)The fault code status displayed by INSITE? electronic service 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 INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Possible causes:
1) A malfunctioning relay
2) A short circuit to ground in the engine harness
3) An open circuit in the engine harness