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 FOR AN ACTIVE DTC
1. Start the engine and allow it to idle.
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 Starter Relay circuit DTCs in the PCM or BCM active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to 3.2L - DIAGNOSTIC CODE INDEX or BODY CONTROL MODULE (BCM) - DIAGNOSTIC CODE INDEX .
  No
  - Go To 3
CHECK THE (T753) IGNITION CRANK SENSE CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PDC C3 harness connector.
3. Disconnect the PCM C2 harness connector.
4. Check for continuity between ground and the (T753) Ignition Crank Sense circuit at the PDC C3 harness connector.
  Is there continuity between ground and the (T753) Ignition Crank Sense circuit?
  
  Yes
  - Repair the (T753) Ignition Crank Sense circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 4
CHECK THE (T753) IGNITION CRANK SENSE CIRCUIT FOR AN OPEN/HIGH RESISTANCE
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.
1. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
2. Measure the resistance of the (T753) Ignition Crank Sense circuit between the PDC C3 harness connector and the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the (T753) Ignition Crank Sense circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
CHECK THE IGNITION CRANK SENSE CIRCUIT BETWEEN STARTER RELAY 2 AND THE PDC CONNECTOR FOR AN OPEN/HIGH RESISTANCE
1. Reconnect the PDC C3 harness connector.
2. Remove Starter Relay 2 from the PDC.
3. Measure the resistance between the Starter Relay 2 connector (terminal 87) and the (T753) Ignition Crank Sense circuit at the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Check all fuses in the PDC. If a fuse is found to be open, replace the and retest. If no problems are found with the fuses, replace the PDC in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
CHECK THE INTERNAL CIRCUIT BETWEEN STARTER RELAY 1 AND STARTER RELAY 2 FOR AN OPEN/HIGH RESISTANCE
1. Remove Starter Relay 1 from the PDC.
2. Measure the resistance between Starter Relay 1 connector (terminal 87) and Starter Relay 2 (terminal 30).
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 7
  No
  - Replace the PDC in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
CHECK THE BATTERY SUPPLY TO STARTER RELAY 1 FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, probe the battery supply to the Starter Relay 1 connector (terminal 30).
  NOTE:
  Compare the brightness to that of a connection direct to battery.
  
  Is the test light illuminated and bright?
  
  Yes
  - Go To 8
  No
  - Check all fuses in the PDC. If a fuse is found to be open, replace the and retest. If no problems are found with the fuses, replace the PDC in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
CHECK STARTER RELAY 1 FOR PROPER OPERATION
1. Turn the ignition off.
2. Reconnect the PCM C2 harness connector.
3. Reinstall Starter Relay 1.
4. Replace Starter Relay 2 with a known good relay.
5. Turn the ignition on.
6. With the scan tool, erase DTCs.
7. Attempt to perform a key start of the engine.
8. With the scan tool, read DTCs.
  Did the DTC return as active or pending?
  
  Yes
  - Replace the Starter Relay 1.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 9
CHECK STARTER RELAY 2 FOR PROPER OPERATION
1. Turn the ignition off.
2. Reinstall Starter Relay 2.
3. Replace Starter Relay 1 with a known good relay.
4. Turn the ignition on.
5. With the scan tool, erase DTCs.
6. Attempt to perform a key start of the engine.
7. With the scan tool, read DTCs.
  Did the DTC return as active or pending?
  
  Yes
  - Replace the Starter Relay 2.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 10
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, 3.2L .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .