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Home >> Jeep >> 2009 >> Commander Overland, 4WD >> Repair and Diagnosis (Single Page) >> Transmission >> Transfer Case >> (Final Drive Control Module (FDCM) - Electrical Diagnostics) >> DTC Troubleshooting >> C1403-Transfer Case Range Position Sensor Performance >> Diagnostic Test
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Diagnostic Test

  1. DTC IS ACTIVE 
    1. Ignition on, engine not running.
      NOTE: Repair any system undervoltage or overvoltage DTCs that are set in this module before proceeding.
    2. With the scan tool, read DTCs.

      Is the DTC status Active at this time?

      Yes 

      • Go to step  2

      No 

      • Go to step  10
  2. (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT VOLTAGE 
    Fig 1: Checking Drivetrain 5 Volt Supply Circuit Voltage
    GC0120020Courtesy of CHRYSLER LLC
    1. Turn the ignition off to the lock position
    2. Disconnect the Transfer Case Motor harness connector.
    3. Ignition on, engine not running.
    4. Measure the voltage of the (K504) Drivetrain 5-volt Supply circuit.

      Select the displayed voltage reading:

      Voltage greater than 5.5 volts. 

      Voltage between 4.5 and 5.5 volts. 

      • Go to step  5

      Voltage less than 4.5 volts. 

      • Go to step  3
  3. (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT HIGH RESISTANCE 
    Fig 2: Checking Drivetrain 5 Volt Supply Circuit High Resistance
    GC0120021Courtesy 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 

      No 

      • Go to step  4
  4. (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND 
    Fig 3: Checking Drivetrain 5 Volt Supply Circuit Shorted To Ground
    GC0120022Courtesy of CHRYSLER LLC
    1. Measure the resistance between ground and the (K504) Drivetrain 5-volt Supply circuit.

      Is the resistance below 5.0 ohms?

      Yes 

      No 

  5. TRANSFER CASE MOTOR 
    Fig 4: Checking Transfer Case Motor
    GC0120023Courtesy 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 (K594) Drivetrain Sensor Return circuit.
    3. Ignition on, engine not running.
    4. With the scan tool, read the T-Case Position Sensor voltage.
    5. The displayed voltage should be approximately 0.0 volts with the jumper wire in place.

      Does the voltage display as described?

      Yes 

      No 

      • Go to step  6
  6. (T313) MODE SENSOR SIGNAL CIRCUIT HIGH RESISTANCE 
    Fig 5: Checking Mode Sensor Signal Circuit High Resistance
    GC0120024Courtesy 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 Final Drive Control Module C2 harness connector.

      Is the resistance above 5.0 ohms?

      Yes 

      No 

      • Go to step  7
  7. (T313) MODE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 6: Checking Mode Sensor Signal Circuit Shorted To Ground
    GC0120025Courtesy of CHRYSLER LLC
    1. Measure the resistance between ground and the (T313) Mode Sensor Signal circuit.

      Is the resistance below 5.0 ohms?

      Yes 

      No 

      • Go to step  8
  8. (T313) MODE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 7: Checking Mode Sensor Signal Circuit Shorted To Voltage
    GC0120026Courtesy of CHRYSLER LLC
    1. Ignition on, engine not running
    2. Measure the voltage of the (T313) Mode Sensor Signal circuit.

      Is there any voltage present?

      Yes 

      No 

      • Go to step  9
  9. (K594) DRIVETRAIN SENSOR RETURN CIRCUIT HIGH RESISTANCE 
    Fig 8: Checking Drivetrain Sensor Return Circuit High Resistance
    GC0120027Courtesy 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 

      No 

  10. 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.
    5. While monitoring the scan tool data relative to this circuit, move the selector switch to each position several times.
    6. Look for the data to change other than as expected or for the DTC to reset.

      Were any problems found?

      Yes 

      No 

      • Test complete.