Cummins ISB6.7 CM2150 (2007-09) Fault Code: 1973 PID: SPN: 3245 FMI: 0 Exhaust Gas Temperature 3 – Data Valid but Above Normal Operational Range – Most Severe Level. The aftertreatment diesel particulate filter outlet temperature sensor reading has exceeded the maximum engine protection temperature limit.

This fault code is logged when the ECM has detected a high temperature condition in the aftertreatment system and active regeneration of the aftertreatment diesel particulate filter is occurring. The fault code indicates that a secondary fuel source is entering the aftertreatment system and is creating a temperature increase across the aftertreatment diesel particulate filter.

Possible causes:

1)Excessive engine oil or diesel fuel being introduced into the exhaust system from the engine
2)A damaged engine fuel injector causing unburned diesel fuel to enter the exhaust system
3)The aftertreatment diesel particulate filter outlet temperature sensor failed in-range
4)An in-range engine sensor malfunction has occurred, causing excessive fuel to enter the exhaust system.

The aftertreatment system must be inspected after making the appropriate repair outlined in this fault code troubleshooting tree. Progressive damage to the aftertreatment system may have occurred. Remove the exhaust aftertreatment system from the vehicle for potential damage and inspect for reuse.

Possible repairs:

1)If no short is found, replace the temperature sensor that is reading higher or lower than the other sensors.
2)Replace the injector, if necessary.
3)Repair or replace any components that caused the engine oil or diesel fuel contamination.
4)If black smoke is present, inspect the aftertreatment system for possible damage.
5)If necessary, calibrate the ECM.