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, recalibrate the ECM.

Possible causes:

1)A signal circuit open or shorted to ground in the engine harness or sensor
2)A supply wire open or shorted to ground
3)A malfunctioning EGR differential pressure sensor.

Possible repairs:

1)Replace the ECM.
2)Replace the EGR valve delta pressure sensor.
3)Replace the engine harness. Refer to Procedure 019-043 (Engine Wiring Harness) in Section 19.
4)Repair the OEM harness