DESCRIPTION:
This fault code sets when the Aftertreatment Control Module (ACM) detects that the Selective Catalyst Reduction (SCR) outlet temperature sensor reading and SCR outlet model temperature is greater than 70°C (158°F).

MONITORED PARAMETER:
SCR outlet temperature.

TYPICAL ENABLING CONDITIONS:
1. Exhaust flow greater than 600 Kg/hr.
2. Coolant temperature greater than 60°C (140°F).
3. Non-regen mode.

MONITOR SEQUENCE:
None

EXECUTION FREQUENCY:
Continuous when enabling conditions met.

TYPICAL DURATION:
2 seconds

DASH LAMPS:
MIL

ENGINE REACTION:
Derate 25%

VERIFICATION:
SCR efficiency test.

NOTE: Monitor the DOC outlet, DPF outlet, SCR inlet, and SCR outlet temps. If they are no close together, the one that is off is the failure sensor.

PROBABLE CAUSES:
1. Check all 4 temp sensors mentioned above at the connections and harness.
2. SCR inlet temp sensor.
3. SCR outlet temp sensor.