Diagnostic Test

WARNING: This page is about a different car, the 2009 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

DTC IS ACTIVE
NOTE: Diagnose and repair any system voltage or Transfer Case related DTCs in the FDCM before continuing with this test.
1. Ignition on, engine running.
2. With the scan tool, clear stored DTCs.
3. Test drive the vehicle.
4. During the test drive, move the Transfer Case Selector Switch to each position several times in accordance with the Service Information.
5. With the scan tool, read DTCs.
  Does this DTC reset?
  
  Yes
  - Go to step 2
  No
  - Go to step 7
TRANSFER CASE POSITION SENSOR VOLTAGE

Fig 1: Checking Transfer Case Motor
Courtesy of CHRYSLER LLC
1. Turn the ignition off to the lock position.
2. Disconnect the Transfer Case Motor harness connector.
3. Connect a jumper wire between the (T313) Mode Sensor Signal circuit and the (K594) Drivetrain Sensor Return circuit.
4. Ignition on, engine running.
5. With the scan tool, read the T-Case Position Sensor voltage.
6. The displayed voltage should be approximately 0.0 volts with the jumper wire in place.
  Does the voltage display as described?
  
  Yes
  - Replace the Transfer Case Clutch in accordance with the Service Information.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure
  No
  - Go to step 3
TRANSFER CASE POSITION SENSOR VOLTAGE

Fig 2: Checking Transfer Case Position Sensor Voltage
Courtesy of CHRYSLER LLC
1. Turn the ignition off to the lock position.
2. Connect a jumper wire between the (T313) Mode Sensor Signal circuit and the (K504) Drivetrain 5 Volt Supply circuit in the Transfer Case Motor harness connector.
3. Ignition on, engine running.
4. With the scan tool, monitor the T-Case Position Sensor voltage in the FDCM.
  Is the voltage between 4.8 volts and 5.2 volts?
  
  Yes
  - Replace or Repair the Transfer Case Clutch in accordance with the Service Information.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure
  No
  - Go to step 4
(K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT HIGH RESISTANCE

Fig 3: Checking Drivetrain 5 Volt Supply Circuit High Resistance
Courtesy of CHRYSLER LLC
1. Turn the ignition off to the lock position
2. Disconnect the Final Drive Control Module C2 harness connector.
3. Measure the resistance of the (K504) Drivetrain 5 Volt Supply circuit between the Transfer Case Motor harness connector and the Final Drive Control Module C2 harness connector.
  Is the resistance above 5.0 ohms?
  
  Yes
  - Repair the high resistance in the (K504) Drivetrain 5 Volt Supply circuit.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure .
  No
  - Go to step 5
(T313) MODE SENSOR SIGNAL CIRCUIT HIGH RESISTANCE

Fig 4: Checking Mode Sensor Signal Circuit High Resistance
Courtesy of CHRYSLER LLC
1. Turn the ignition off to the lock position
2. Disconnect the Final Drive Control Module C2 harness connector.
3. Measure the resistance of the (T313) Mode Sensor Signal circuit between the Transfer Case Motor harness connector and the Final Drive Control Module C2 harness connector.
  Is the resistance above 5.0 ohms?
  
  Yes
  - Repair the high resistance in the (T313) Mode Sensor Signal circuit.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure .
  No
  - Go to step 6
(K594) DRIVETRAIN SENSOR RETURN CIRCUIT HIGH RESISTANCE

Fig 5: Checking Drivetrain Sensor Return Circuit High Resistance
Courtesy of CHRYSLER LLC
1. Measure the resistance of the (K594) Drivetrain Sensor Return circuit between the Transfer Case Motor harness connector and the Final Drive Control Module C2 harness connector.
  Is the resistance below 5.0 ohms?
  
  Yes
  - Replace the Final Drive Control Module (FDCM) in accordance with the Service Information.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure .
  No
  - Repair the high resistance in the (K594) Drivetrain Sensor Return circuit.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure .
INTERMITTENT WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the SYSTEM WIRING DIAGRAMS as a guide, inspect the wiring and connectors.
3. While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors.
4. Look for the data to change or for the DTC to reset during the wiggle test.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the TRANSFER CASE VERIFICATION. See DTC-Based Diagnostics/MODULE, Final Drive Control (FDCM) - Standard Procedure .
  No
  - Test complete.