Diagnostic Test

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, with the scan tool, 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 10.0 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 CONDITION .
CHECK FOR 5-VOLT REFERENCE DTCS
NOTE:
Although two-wire sensors do not use the 5-Volt Reference circuit directly, some PCMs use a common source to power the 5-Volt Reference circuit and the two-wire sensors. If the 5-Volt Reference circuit is shut down by the PCM internally for protection due to a short, it can cause faults to set against some two-wire sensors.
1. Refer to the recorded DTCs.
  Are there any 5-Volt Reference DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to 3.6L - DIAGNOSTIC CODE INDEX .
  No
  - Go To 3
CHECK THE (K683) EGR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the EGR Valve harness connector.
3. Disconnect the PCM C2 harness connector.
4. Check for continuity between ground and the (K683) EGR Signal circuit at the EGR Valve harness connector.
  Is there continuity between ground and the (K683) EGR Signal circuit?
  
  Yes
  - Repair the (K683) EGR Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (K683) EGR SIGNAL CIRCUIT FOR A SHORT TO THE (K918) SENSOR GROUND CIRCUIT
1. Check for continuity between the (K683) EGR Signal circuit and the (K918) Sensor Ground circuit at the EGR Valve harness connector.
  Is there continuity between the (K683) EGR Signal circuit and the (K918) Sensor Ground circuit?
  
  Yes
  - Repair the (K683) EGR Signal circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE EGR VALVE FOR PROPER OPERATION
1. Reconnect the PCM C2 harness connector.
2. Connect a jumper between the (F855) 5-Volt Supply circuit and the (K683) EGR Signal circuit at the EGR Valve harness connector.
3. Turn the ignition on.
4. With the scan tool, read active DTCs.
  NOTE:
  The P0406-EGR POSITION SENSOR CIRCUIT HIGH DTC should be active or pending with the jumper in place.
  
  Does the DTC display as described above?
  
  Yes
  - Replace the EGR Valve in accordance with the Service Information. The EGR VALVE REPLACED routine must be performed after replacing or cleaning the EGR Valve to reset the zero learn position. Failure to do so will cause a false failure and the P1404 DTC to set. With the scan tool, perform the EGR VALVE REPLACED routine.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .