Diagnostic Test

WARNING: This page is about a different car, the 2016 Jeep Wrangler and 2015 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. Diagnose and repair any other active component or circuit DTCs before continuing with this procedure.
2. Turn the ignition on.
3. With the scan tool, read DTCs and record on the repair order. Copy DTC and Freeze Frame information.
4. 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.
5. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
EXHAUST LEAK
NOTE:
A thorough exhaust leak test should 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 diagnostic procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .
  Were any problems found?
  
  Yes
  - Repair the exhaust leak(s) in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECKING THE FUEL DELIVERY SYSTEM
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic 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 POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECKING THE OXYGEN SENSOR OPERATION
1. Perform the diagnostic procedure for CHECKING THE OXYGEN SENSOR OPERATION. Refer to CHECKING THE OXYGEN SENSOR OPERATION .
  Were any problems found?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECKING THE ENGINE MECHANICAL SYSTEM
1. Perform the diagnostic procedure for CHECKING THE ENGINE MECHANICAL SYSTEM. Refer to CHECKING THE ENGINE MECHANICAL SYSTEM .
  Were any problems found?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all PCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. 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.
6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Powertrain Control Module in accordance with the Service information. Refer to MODULE, POWERTRAIN CONTROL [EHD, ERB], REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  - Test complete.