Diagnostic Test

WARNING: This page is about a different car, the 2020 Jeep Renegade. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. Start the engine.
2. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
3. With the scan tool, read DTCs and record on the repair order.
  NOTE:
  It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
  
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are there any O2 Sensor circuit, MAP Sensor, Fuel Injector, Ignition Coil DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DIAGNOSTIC CODE INDEX .
  No
  - Go To 3
CHECK THE EXHAUST SYSTEM FOR RESTRICTIONS
NOTE:
While this fault could set due to a faulty O2 Sensor or wiring, it is more likely to set due to a mechanical, fuel system or air handling issue.
1. Start the engine and check for good exhaust flow at the tailpipe.
2. Visually inspect the exhaust system for any damage that could cause a restriction.
  Were any problems found?
  
  Yes
  - Repair the Exhaust system in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK THE MAP SENSOR OPERATION
1. Perform the CHECKING THE MAP SENSOR OPERATION test procedure. Refer to CHECKING THE MAP SENSOR PERFORMANCE .
  Were any problems found?
  
  Yes
  - Repair the MAP Sensor problem in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE MAF SENSOR OPERATION
1. Start the engine. Warm the engine up to operating temperature.
2. With the scan tool, read the MAF Sensor value with the engine at idle.
  Does the Mass Air Flow Sensor read approximately 3.0 - 9.0 g/sec?
  
  Yes
  - Go To 6
  No
  - Repair any leaks or restrictions in the Intake Air System. If no leaks or restrictions are found, replace the Mass Air Flow Sensor in accordance with the Service Information. Refer to SENSOR, MANIFOLD AIR PRESSURE (MAP), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE PURGE SOLENOID OPERATION
1. Turn the ignition off.
2. Disconnect the hoses at the Purge Solenoid.
3. Using a hand vacuum pump, apply 5.0 in. Hg. to the "ENGINE" side of the Purge Solenoid.
  Did the Purge Solenoid hold vacuum for a minimum of 15 seconds? (Connect the vacuum hoses before continuing.)
  
  Yes
  - Go To 7
  No
  - Repair the poor connections at the Evap Purge Solenoid and Powertrain Control Module connectors. If the connections are not the problem, replace the EVAP Purge Solenoid in accordance with the Service Information. Refer to the appropriate service information .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE FUEL DELIVERY SYSTEM
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
  Were any problems found?
  
  Yes
  - Perform the appropriate repair in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
CHECK FOR ENGINE MECHANICAL CONDITIONS
1. Check for any of the following conditions/mechanical problems:
  - AIR INDUCTION SYSTEM - must be free from restrictions.
  - ENGINE VALVE TIMING - must be within specifications.
  - ENGINE COMPRESSION - must be within specifications.
  - FUEL - must be free of contamination.
  - FUEL INJECTOR - if a Fuel Injector is suspected of leaking or abnormal spray pattern, remove the fuel rail with the injectors intact. Energize the fuel pump to maintain fuel pressure in the fuel rail. Check for any fuel leakage before the suspect injector is actuated. Actuate the suspect Fuel Injector(s) with the scan tool and inspect the fuel spray pattern for abnormalities. Compare with the other injectors.
  Are there any engine mechanical problems?
  
  Yes
  - Repair the engine mechanical problems in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 9
CHECK THE UPSTREAM O2 SENSOR CIRCUITS FOR A SHORT TO GROUND AND AN OPEN
1. Disconnect the Upstream O2 Sensor harness connector.
2. Disconnect the PCM C2 harness connector.
  CAUTION:
  Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
3. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
4. Check the Upstream O2 Sensor circuits;
  - for a short to ground in the wiring between the O2 Sensor harness connector and the PCM C2 harness connector.
  - for an open or high resistance in the wiring between the O2 Sensor harness connector and the PCM C2 harness connector.
  Are the Upstream O2 Sensor circuits shorted to ground or high resistance?
  
  Yes
  - Repair the Upstream O2 Sensor circuits for a short to ground or an open.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 10
CHECK THE OXYGEN SENSOR OPERATION
1. Perform the CHECKING THE OXYGEN SENSOR OPERATION test procedure. Refer to CHECKING THE OXYGEN SENSOR PERFORMANCE .
  Were any problems found?
  
  Yes
  - Repair the Oxygen Sensor problem in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 11
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 AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Repair the poor connections.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .