Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK THE EXHAUST SYSTEM FOR LEAKS
NOTE:
A thorough exhaust leak test must be completed before removing an O2 Sensor or any other part from the exhaust system. Do not remove any parts before an exhaust leak check has been completed.

NOTE:
An exhaust leak may cause downstream fuel adaptives to rail out, resulting in a false O2 Sensor failure
1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .
  Were any problems found?
  
  Yes
  - Go To 8
  No
  - Go To 2
CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, read DTCs. Copy DTC and Freeze Frame information.
3. Start the engine and allow it to reach operating temperature.
  WARNING:
  When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
  
  NOTE:
  Attempt to operate the vehicle under conditions similar to which the DTC was set.
  
  NOTE:
  It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.
4. With a scan tool, read DTCs and record on the repair order.
  Is the DTC active?
  
  Yes
  - Go To 3
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are there any active component or circuit DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to 3.2L - DIAGNOSTIC CODE INDEX .
  No
  - Go To 4
CHECK THE FUEL DELIVERY SYSTEM FOR PROPER OPERATION
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
  Were any problems found?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 5
CHECK THE OXYGEN SENSOR FOR PROPER OPERATION
1. Perform the diagnostic procedure for CHECKING THE OXYGEN SENSOR OPERATION. Refer to DIAGNOSIS AND TESTING .
  Were any problems found?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - Go To 6
CHECK THE ENGINE MECHANICAL SYSTEM FOR DAMAGE
1. Perform the CHECKING THE ENGINE MECHANICAL SYSTEM test procedure. Refer to CHECKING THE ENGINE MECHANICAL SYSTEM .
  Were any problems found?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 7
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, 2.4L/3.2L .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
EXHAUST LEAK
1. Repair the exhaust leak(s) as necessary.
2. Start the engine and allow it to reach operating temperature.
3. Test drive the vehicle at a steady 80 km/h (50 mph) to 97 km/h (60 mph) for at least 10 minutes.
4. Stop the vehicle and turn the ignition off for 5 seconds.
5. Test drive the vehicle again at a steady 80 km/h (50 mph) to 97 km/h (60 mph) for at least 10 minutes.
6. Stop the vehicle.
7. With the scan tool, read DTCs.
  Does this DTC reset as a pending or stored DTC?
  
  Yes
  - Retest. Go To 1
  No
  - Test Complete.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .