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 and allow it to reach normal operating temperature.
2. 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 .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are there any system voltage or sensor supply voltage DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DIAGNOSTIC CODE INDEX .
  No
  - Go To 3
CHECK THE (K157) MAF SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Mass Air Flow Sensor connector.
3. Turn the ignition on.
4. Measure the voltage on the (K157) MAF Signal circuit in the Mass Air Flow Sensor harness connector.
  Is the voltage reading above 5.2 volts?
  
  Yes
  - Repair the (K157) MAF Signal circuit for a short to voltage.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (K157) MAF SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
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) to the engine harness side of the PCM C2 harness connector. Do not connect the GPEC Diagnostic Adaptor to the PCM.
4. Measure the resistance of the (K157) MAF Signal circuit between the Mass Air Flow Sensor harness connector and the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the (K157) MAF Signal circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (K900) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K900) Sensor Ground circuit between the Mass Air Flow Sensor harness connector and the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the (K900) Sensor Ground circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
REPLACE THE MASS AIR FLOW SENSOR AND RETEST FOR DTC
1. Replace the Mass Air Flow Sensor in accordance with the Service Information.
2. Connect the MAF Sensor and PCM C2 harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the recorded Freeze Frame Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
6. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 7
  No
  - Replacing the MAF Sensor repaired the fault.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
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
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .