Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
NOTE:
During cold ambient temperatures, it may be necessary to test drive the vehicle for an extended period to properly cycle the fail conditions for this DTC.

NOTE:
During extremely cold ambient temperatures, it may be necessary to perform an overnight soak of the vehicle at shop temperatures before beginning this Test Step.
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 75.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .
VERIFY THE CORRECT APPLICATION AND LOCATION OF THE NOX SENSORS
1. Verify that the correct application NOx Sensors are being used and properly connected in their correct locations.
  Are the NOx Sensors configured correctly?
  
  Yes
  - Go To 3
  No
  - Install the correct NOx Sensors in the correct locations.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are the P220A, P220B, U029D, or U029E DTCs or any aftertreatment DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DTC INDEX (1 OF 2) and/or DTC INDEX (2 OF 2) .
  No
  - Go To 4
CHECK THE EXHAUST SYSTEM FOR LEAKS
1. Visually inspect the entire exhaust system for signs of a leak.
  Were any exhaust leaks found?
  
  Yes
  - Perform the appropriate repair.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE NOX SENSOR 1/2 WIRING HARNESS AND CONNECTOR
NOTE:
The NOx Sensor consists of a Module and a Probe (with a harness in between) which cannot be serviced separately. They are replaced as one unit.

CAUTION:
Do not attempt to disconnect the NOx harness connector between the NOx Sensor Probe and the NOx Sensor Module. This connector is permanently attached to the NOx Sensor Module. Any attempt to remove this connector will permanently damage the NOx Sensor.
1. Using the wiring diagram/schematic as a guide, inspect the (vehicle harness) wiring and connectors between the NOx Sensor 1/2 (Module) and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .
  No
  - Replace the NOx Sensor 1/2 in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .