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Diagnostic Test

  1. 1) DTC IS ACTIVE 
    NOTE: This DTC sets when the Final Drive Control Module detects excessive voltage fluctuation on the Mode Sensor Signal circuit. Perform a thorough inspection of all wiring and connectors between the sensor and the control module.

    Ignition on, engine not running.

    With the scan tool, read DTCs in the Final Drive Control Module.

    Is the status Active for this DTC? 

    Yes 

    1. Go to  2).

    No 

    1. Go to  13).
  2. 2) (T504) DRIVETRAIN 5 VOLT SUPPLY VOLTAGE ERRATIC 
    Fig 1: Checking Drivetrain 5 Volt Supply Circuit Voltage
    GC0027378Courtesy of CHRYSLER LLC
    NOTE: This DTC sets when the Final Drive Control Module detects excessive voltage fluctuation on the Mode Sensor Signal circuit. Perform a thorough inspection of all wiring and connectors between the sensor and the control module.

    Turn the ignition off to the lock position

    Disconnect the Transfer Case Motor harness connector.

    Ignition on, engine not running.

    Measure the voltage of the (T504) Drivetrain 5-volt Supply circuit.

    NOTE: Voltage should be approximately 5.0 volts and steady. Compare any slight fluctuations found to a known good circuit in order to verify voltmeter functionality.

    Is the voltage approximately 5.0 volts and steady? 

    Yes 

    1. Go to  6).

    No 

    1. Go to  3).
  3. 3) (T504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT INTERMITTENT SHORT TO VOLTAGE 
    Fig 2: Checking Drivetrain 5 Volt Supply Circuit Voltage
    GC0027378Courtesy of CHRYSLER LLC

    Turn the ignition off to the lock position

    Disconnect the Final Drive Control Module C2 harness connector.

    Ignition on, engine not running.

    Measure the voltage of the (T504) Drivetrain 5-volt Supply circuit.

    Monitor the voltmeter while performing a wiggle test on the wiring harness and connectors.

    Is any voltage detected on the circuit during the wiggle test? 

    Yes 

    1. Repair the (T504) Drivetrain 5-volt Supply circuit for an intermittent short to voltage.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  4).
  4. 4) (T504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT HIGH RESISTANCE 
    Fig 3: Checking Drivetrain 5 Volt Supply Circuit High Resistance
    GC0027379Courtesy of CHRYSLER LLC

    Measure the resistance of the (T504) Drivetrain 5-volt Supply circuit between the Transfer Case Motor harness connector and the Final Drive Control Module C2 harness connector.

    Monitor the ohmmeter while performing a wiggle test on the wiring harness and connectors.

    Is the resistance ever above 5.0 ohms during the wiggle test? 

    Yes 

    1. Repair the (T504) Drivetrain 5-volt Supply circuit for an intermittent open circuit or high resistance.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  5).
  5. 5) (T504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT INTERMITTENT SHORT TO GROUND 
    Fig 4: Checking Drivetrain 5 Volt Supply Circuit For Short To Ground
    GC0027380Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (T504) Drivetrain 5-volt Supply circuit.

    Monitor the ohmmeter while performing a wiggle test on the wiring harness and connectors.

    Is the resistance ever below 5.0 ohms during the wiggle test? 

    Yes 

    1. Repair the (T504) Drivetrain 5-volt Supply circuit for an intermittent short to ground.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Replace the Final Drive Control Module in accordance with the Service Information.
    2. Perform TRANSFER CASE VERIFICATION TEST .
  6. 6) T-CASE POSITION SENSOR VOLTAGE 
    Fig 5: Checking Transfer Case Motor Signal Circuit
    GC0027381Courtesy of CHRYSLER LLC

    Turn the ignition off to the lock position

    Reconnect the Final Drive Control Module C2 harness connector.

    Connect a jumper wire between the (T313) Mode Sensor Signal circuit and the (K594) Drivetrain Sensor Return circuit in the Transfer Case Motor harness connector.

    Ignition on, engine not running.

    With the scan tool read the T-Case Position Sensor Voltage in the Final Drive Control Module while performing a wiggle test on the wiring and connectors between the sensor and the control module.

    NOTE: Voltage should be approximately 0.0 volts and steady.

    Is the T-Case Position Sensor Voltage approximately 0.0 volts and steady? 

    Yes 

    1. Go to  12).

    No 

    1. Go to  7).
  7. 7) (T313) MODE SENSOR SIGNAL CIRCUIT INTERMITTENT SHORT TO VOLTAGE 
    Fig 6: Checking Mode Sensor Signal Circuit For Short To Voltage
    GC0027384Courtesy of CHRYSLER LLC
    NOTE: Remove the previously installed jumper wire.

    Turn the ignition off to the lock position

    Disconnect the Final Drive Control Module C2 harness connector.

    Ignition on, engine not running.

    Measure the voltage of the (T313) Mode Sensor Signal circuit.

    Monitor the voltmeter while performing a wiggle test on the wiring harness and connectors.

    Is any voltage detected on the circuit during the wiggle test? 

    Yes 

    1. Repair the (T313) Mode Sensor Signal circuit for an intermittent short to voltage.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  8).
  8. 8) (K594) DRIVETRAIN SENSOR RETURN CIRCUIT INTERMITTENT SHORT TO VOLTAGE 
    Fig 7: Checking Drivetrain Sensor Return Circuit For Intermittent Short To Voltage
    GC0027402Courtesy of CHRYSLER LLC

    Measure the voltage of the (K594) Drivetrain Sensor Return circuit.

    Monitor the voltmeter while performing a wiggle test on the wiring harness and connectors.

    Is any voltage detected on the circuit during the wiggle test? 

    Yes 

    1. Repair the (K594) Drivetrain Sensor Return circuit for an intermittent short to voltage.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  9).
  9. 9) (T313) MODE SENSOR SIGNAL CIRCUIT HIGH RESISTANCE 
    Fig 8: Checking Mode Sensor Signal Circuit For Open Or High Resistance
    GC0027382Courtesy of CHRYSLER LLC

    Turn the ignition off to the lock position

    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.

    Monitor the ohmmeter while performing a wiggle test on the wiring harness and connectors.

    Is the resistance ever above 5.0 ohms during the wiggle test? 

    Yes 

    1. Repair the (T313) Mode Sensor Signal circuit for an intermittent open circuit or high resistance.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  10).
  10. 10) (K594) DRIVETRAIN SENSOR RETURN CIRCUIT HIGH RESISTANCE 
    Fig 9: Checking Drivetrain Sensor Return Circuit High Resistance
    GC0027385Courtesy of CHRYSLER LLC

    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.

    Monitor the ohmmeter while performing a wiggle test on the wiring harness and connectors.

    Is the resistance ever above 5.0 ohms during the wiggle test? 

    Yes 

    1. Repair the (K594) Drivetrain Sensor Return circuit for an intermittent open circuit or high resistance.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Go to  11).
  11. 11) (T313) MODE SENSOR SIGNAL CIRCUIT INTERMITTENT SHORT TO GROUND 
    Fig 10: Checking Mode Sensor Signal Circuit For Short To Ground
    GC0027383Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (T313) Mode Sensor Signal circuit.

    Monitor the ohmmeter while performing a wiggle test on the wiring harness and connectors.

    Is the resistance ever below 5.0 ohms during the wiggle test? 

    Yes 

    1. Repair the (T313) Mode Sensor Signal circuit for an intermittent short to ground.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Replace the Final Drive Control Module in accordance with the Service Information.
    2. Perform TRANSFER CASE VERIFICATION TEST .
  12. 12) TRANSFER CASE MOTOR 
    NOTE: This DTC sets when the Final Drive Control Module detects excessive voltage fluctuation on the Mode Sensor Signal circuit. Perform a thorough inspection of all wiring and connectors between the sensor and the control module.

    Using the schematic as a guide, inspect the Final Drive Control Module power and ground circuits.

    Were any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Replace the Transfer Case Motor in accordance with the Service Information.
    2. Perform TRANSFER CASE VERIFICATION TEST .
  13. 13) INTERMITTENT WIRING AND CONNECTORS 

    The conditions necessary to set this DTC are not present at this time.

    Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.

    While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors.

    Look for the data to change or for the DTC to reset during the wiggle test.

    Were any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform TRANSFER CASE VERIFICATION TEST .

    No 

    1. Test complete.
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