Cummins ISC CM2150 (2007-09) Fault Code: 2638 PID: SPN: 3050 FMI: 13 Catalyst Efficiency - Out of Calibration. The temperature increase across the aftertreatment diesel oxidation catalyst is lower than expected.

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM. If necessary, calibrate the ECM.

This fault code is logged when the electronic control module (ECM) has calculated DOC efficiency to be less than required to successfully complete a regeneration.

Possible causes:

1)Soot plugging the front face of the aftertreatment diesel oxidation catalyst
2)Engine oil or fuel contamination of the aftertreatment diesel oxidation catalyst
3)Cracked or contaminated aftertreatment diesel oxidation catalyst
4)Damage in the aftertreatment fuel injection system
5)Leaking exhaust system between the turbocharger and the diesel oxidation catalyst
6)An in-range malfunction of the aftertreatment diesel oxidation catalyst or the aftertreatment diesel particulate filter inlet temperature sensor can cause this fault code. Make sure there are not any fault codes related to the aftertreatment temperature sensors before following this troubleshooting tree.

Possible repairs:

1)If necessary, calibrate the ECM.
2)Repair or replace the damaged or leaking exhaust system components
3)Replace the aftertreatment DOC.