DESCRIPTION:
Outlet NOx sensor is drifted.

MONITORED PARAMETER:
1. Selective catalyst reduction (SCR) outlet NOx.
2. Engine speed between 1000 to 2000 rpm.
3. Engine load between 25 to 100%.

TYPICAL ENABLING CONDITIONS:
1. SCR temperature greater than 390°C (734°F) for 10 seconds.
2. Inlet NOx to outlet NOx deviation greater than 200 ppm.

MONITOR SEQUENCE:
Once per drive cycle.

EXECUTION FREQUENCY:
Continuous when enabling conditions met.

TYPICAL DURATION:
20 seconds

DASH LAMPS:
None

ENGINE REACTION:
Dosing is disabled

VERIFICATION:
Parked regeneration

NOTE: If any other EGR codes are active, fix those first.

PROBABLE CAUSES:
1. Check the aftertreatment system for leaks/damage.
2. Perform a high idle regeneration with the metering valve or dosing unit disconnected.