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 CONDITION
1. Force the Radiator Fan to operate to verify an active condition in one of the following ways:
  - Turn the ignition on and actuate the Radiator Fan Module with a scan tool.
  - Start the engine and turn on the A/C System or Defrost.
  - Start the engine and allow it reach operating temperature.
  Is the Radiator Fan Module operating properly?
  
  Yes
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
  No
  - Go To 2
CHECK THE RADIATOR FAN RELAY AND PDC FOR PROPER OPERATION
1. Stop Radiator Fan operation. Leave the ignition on.
2. Using a 12-volt test light connected to ground, back probe the Radiator Fan Relay (K175) Control circuit at the PDC C2 connector.
3. Using a 12-volt test light connected to ground, probe the Radiator Fan Relay (N29) Output circuit at the PDC C2 connector to verify the relay is closing when energized. The test light should illuminate when the relay is closed.
  NOTE:
  The relay may also make an audible click when closing.
  
  Does the Radiator Fan Relay close when the control circuit is grounded?
  
  Yes
  - Go To 3
  No
  - Go To 7
ISOLATE AND CHECK THE RADIATOR FAN RELAY (K175) CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT AT THE PCM HARNESS CONNECTOR
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Disconnect the PDC C2 harness connector.
4. Check for continuity between the Radiator Fan Relay (K175) Control circuit and all other circuits at the PCM C1 harness connector.
  Is there continuity between the Radiator Fan Relay (K175) Control circuit and any other circuit?
  
  Yes
  - Repair the short to the circuit that showed continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 4
CHECK FOR THE (K175) RADIATOR FAN CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Check for continuity between ground and the (K175) Radiator Fan Control circuit at the Radiator Fan at the PDC C2 harness connector.
  Is there continuity between the ground and the (K175) Radiator Fan Control circuit?
  
  Yes
  - Repair the (K175) Radiator Fan Control circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Go To 5
CHECK THE (K175) RADIATOR FAN CONTROL 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) to the PCM harness connector.
2. Measure the resistance of the (K175) Radiator Fan Control circuit between the PDC C2 harness connector and the GPEC adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the (K175) Radiator Fan Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
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 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 .
CHECK THE BATTERY SUPPLY VOLTAGE TO THE PDC
1. Using the wiring information as a guide, measure the main Battery supply voltage at the PDC terminal.
  Is Battery voltage present?
  
  Yes
  - Check all fuses in the PDC. If a fuse is found to be open, replace the fuse and retest. If no problems are found with the fuses, replace the Power Distribution Center (PDC) in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .
  No
  - Repair the Battery voltage supply to the PDC for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L .