Diagnostic Test

WARNING: This page is about a different car, the 2012 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY DTC IS ACTIVE
NOTE:
Before continuing with this test, perform the appropriate diagnostic procedure for all other DTCs first.

NOTE:
Verify the harness is not damaged to the WCM and or the TPM Transponders before continuing with this diagnostic procedure.
1. Ignition on, engine not running.
2. With the scan tool, read and record DTCs.
3. With the scan tool, erase DTCs.
4. Cycle the ignition switch.
5. With the scan tool, read DTCs.
  Is the DTC status Active at this time?
  
  Yes
  - Go To 2.
  No
  - Go To 9.
TIRE PRESSURE MONITORING (TPM) TRANSPONDERS

Fig 1: Measuring Voltage Between Fused Ignition Switch Output (Run) Circuit And Ground Circuits At Each TPM Transponder Harness Connectors
Courtesy of CHRYSLER GROUP, LLC

NOTE:
For the proper locations of the TPM Transponders, refer to the appropriate service information.
1. Turn the ignition off to the lock position.
2. Disconnect all of the TPM Transponder harness connectors.
3. Ignition on, engine not running.
4. With a voltmeter measure the voltage between the Fused Ignition Switch Output (Run) circuit and the Ground circuits at each of the TPM Transponder harness connectors.
  Was the voltage within battery voltage (±1 Volt) at each of the TPM Transponders?
  
  Yes
  - Perform the Stored Lost Communication diagnostic procedure. Refer to COMMUNICATION - DIAGNOSIS AND TESTING .
  No
  - Go To 3.
FUSED IGNITION SWITCH OUTPUT (RUN) CIRCUIT OPEN OR HIGH RESISTANCE

Fig 2: Checking Fused Ignition Switch Output (Run) Circuit For An Open Or High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Using a 12-volt test light connect to ground, check the Fused Ignition Switch Output (Run) circuit at all of the TPM Transponder harness connectors.
  NOTE:
  The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
  
  Is the test light illuminated and bright?
  
  Yes
  - Go To 4.
  No
  - Repair the Fused Ignition Switch Output (Run) circuit for an open circuit or high resistance.
  - Perform TPM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
GROUND CIRCUIT(S) OPEN OR HIGH RESISTANCE

Fig 3: Checking Ground Circuit(s) For Open Or High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off to the lock position.
2. Using a 12-volt test light connect to battery voltage, check each of the Ground circuits.
  NOTE:
  The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Go To 5.
  No
  - Repair the Ground circuit(s) for an open circuit or high resistance.
  - Perform TPM VERIFICATION. Refer to STANDARD PROCEDURE .
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO VOLTAGE

Fig 4: Checking COM-LIN Tire Pressure Monitor LAN Circuit For A Short To Voltage
Courtesy of CHRYSLER GROUP, LLC
1. Disconnect the WCM harness connector.
2. Ignition on, engine not running.
3. Measure the voltage between ground and the (D508) COM - LIN Tire Pressure Monitor LAN circuit at all of the TPM Transponder harness connectors.
  Is there any voltage present?
  
  Yes
  - Repair the (D508) COM - LIN Tire Pressure Monitor LAN circuit for a short to voltage.
  - Perform TPM VERIFICATION. Refer to STANDARD PROCEDURE .
  No
  - Go To 6.
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT SHORT TO GROUND

Fig 5: Checking COM-LIN Tire Pressure Monitor LAN Circuit For A Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off to the lock position.
2. Measure the resistance between ground and the (D508) COM - LIN Tire Pressure Monitor LAN circuit at all of the TPM Transponder harness connectors.
  Is the resistance below 5 Ohms?
  
  Yes
  - Repair the (D508) COM - LIN Tire Pressure Monitor LAN circuit for a short to ground.
  - Perform TPM VERIFICATION. Refer to STANDARD PROCEDURE .
  No
  - Go To 7.
(D508) COM - LIN TIRE PRESSURE MONITOR LAN CIRCUIT OPEN OR HIGH RESISTANCE

Fig 6: Checking COM-LIN Tire Pressure Monitor LAN Circuit For Open Or High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance of the (D508) COM-LIN Tire Pressure Monitor LAN circuit between the TPM Transponder harness connectors and the WCM harness connectors.
  Is the resistance below 5 Ohms?
  
  Yes
  - Go To 8.
  No
  - Repair the (D508) COM-LIN Tire Pressure Monitor LAN circuit for an open.
  - Perform TPM VERIFICATION. Refer to STANDARD PROCEDURE .
CHECK FOR ADDITIONAL TIRE PRESSURE MONITORING (TPM) TRANSPONDER COMMUNICATION RELATED DTCs
1. With the scan tool, select Network View and select Advanced.
  Is there more than one module with active DTCs Logged Against the WCM?
  
  Yes
  - Replace the Wireless Control Module (WCM) in accordance with the Service Information.
  - Perform WCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace the Tire Pressure Monitoring (TPM) Transponder in accordance with the Service Information.
  - Perform TPM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
INTERMITTENT TIRE PRESSURE MONITORING (TPM) TRANSPONDER DTC
NOTE:
The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.
1. Check Technical Service Bulletins (TSBs) for any causes that may apply.
2. Review the scan tool Environmental Data (EV Data). If possible, try to duplicate the conditions under which the DTC set.
3. Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
4. If numerous DTCs were set, use a wiring diagram/schematic and look for any common ground or power supply circuits.
5. Turn the ignition off to the lock position.
6. Using the wiring diagram/schematic as a guide, inspect the related wire harness. Disconnect all the related harness connectors. Look for any chafed, pierced, pinched, partially broken wires and broken, bent, pushed out or corroded terminals.
  Were any problems found?
  
  Yes
  - Perform the necessary repairs.
  - Perform TPM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Test complete.