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Transfer Case - Electrical Diagnostics: Diagnosis Jeep Commander I

Transfer Case 1 illustration ~5797 words

DIAGNOSTIC CODE INDEX

DTCDescription
C1400TRANSFER CASE RANGE SELECT SWITCH PERFORMANCE
C1401TRANSFER CASE RANGE SELECT SWITCH CIRCUIT LOW
C1402TRANSFER CASE RANGE SELECT SWITCH CIRCUIT HIGH
C1403TRANSFER CASE RANGE POSITION SENSOR PERFORMANCE
C1404TRANSFER CASE RANGE POSITION SENSOR CIRCUIT LOW
C1405TRANSFER CASE RANGE POSITION SENSOR CIRCUIT HIGH
C1406TRANSFER CASE BRAKE PERFORMANCE
C1407TRANSFER CASE BRAKE CONTROL CIRCUIT LOW
C1408TRANSFER CASE BRAKE CONTROL CIRCUIT HIGH
C140ATRANSFER CASE MOTOR PERFORMANCE
C140DTRANSFER CASE MOTOR CONTROL CIRCUIT OPEN
C140ETRANSFER CASE MOTOR BLOCKED
C140FTRANSFER CASE RANGE POSITION SENSOR ERRATIC PERFORMANCE
C14134 HI/LO SELECT SWITCH CIRCUIT STUCK
C1414NEUTRAL SELECT SWITCH CIRCUIT STUCK
C1415TRANSFER CASE MOTOR "CURRENT" PERFORMANCE
C1438TRANSFER CASE DIFFERENTIAL CLUTCH WORN
C1444TRANSFER CASE MOTOR OVERUSE
C2100BATTERY VOLTAGE LOW (FDCM)
C2101BATTERY VOLTAGE HIGH (FDCM)
C2111DRIVETRAIN SENSOR SUPPLY CIRCUIT LOW (FDCM)
C2112DRIVETRAIN SENSOR SUPPLY CIRCUIT HIGH (FDCM)
C2113DRIVETRAIN SENSOR SUPPLY CIRCUIT OPEN (FDCM)
C2201INTERNAL CONTROLLER (FDCM)
C2206CONFIGURATION ERROR (FDCM)
C230ANEUTRAL INDICATOR CONTROL CIRCUIT LOW
C230BNEUTRAL INDICATOR CONTROL CIRCUIT HIGH
U0401IMPLAUSIBLE DATA RECEIVED FROM ECM (FDCM)
U0402IMPLAUSIBLE DATA RECEIVED FROM TCM (FDCM)
U0415IMPLAUSIBLE DATA RECEIVED FROM ABS (FDCM)
U0429IMPLAUSIBLE DATA RECEIVED FROM SCM (FDCM)
U0431IMPLAUSIBLE DATA RECEIVED FROM FCM (FDCM)

DIAGNOSTIC CODE INDEX

Scheme 39

Scheme 39: Circuit Schematic
Scheme 39: Circuit Schematic

Diagnostic Test

  1. 1) 4WD RANGE SWITCH VOLTAGE LESS THAN 0.2 VOLTS Ignition on, engine not running. NOTE: Repair any system undervoltage or overvoltage DTCs that are set in this module before proceeding. With the scan tool, read the 4WD Range Switch voltage in the Final Drive Control Module. Is the voltage less than 0.2 volts? Yes Go to 2) . No Go to 8) .
  2. 2) TRANSFER CASE SELECTOR SWITCH Turn the ignition off to the lock position Disconnect the Transfer Case Selector Switch harness connector. Connect a jumper wire between the (K504) Drivetrain 5 Volt Supply circuit and the (K977) Mode Select circuit in the Transfer Case Selector Switch harness connector. Ignition on, engine not running. With the scan tool, read the 4WD Range Switch voltage. The switch voltage should be approximately 5.0 volts. Does the voltage display as described? Yes Replace the Transfer Case Selector Switch. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT VOLTAGE Ignition on, engine not running. Measure the voltage of the (K504) Drivetrain 5 Volt Supply circuit. The voltage should be approximately 5.0 volts. Does the voltage display as described? Yes Go to 6) . No Go to 4) .
  4. 4) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND Turn the ignition off to the lock position Disconnect the Final Drive Control Module C2 harness connector. Measure the resistance between ground and the (K504) Drivetrain 5 Volt Supply circuit. Is the resistance less than 5.0 ohms? Yes Repair the (K504) Drivetrain 5 Volt Supply circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 5) .
  5. 5) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT OPEN Measure the resistance of the (K504) Drivetrain 5 Volt Supply circuit between the Transfer Case Selector Switch harness connector and the Final Drive Control Module C2 harness connector. Is the resistance greater than 5.0 ohms? Yes Repair the (K504) Drivetrain 5 Volt Supply circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  6. 6) (K977) MODE SELECT CIRCUIT SHORT TO GROUND Turn the ignition off to the lock position Disconnect the Final Drive Control Module C2 harness connector. Measure the resistance between ground and the (K977) Mode Select circuit. Is the resistance less than 5.0 ohms? Yes Repair the (K977) Mode Select circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 7) .
  7. 7) (K977) MODE SELECT CIRCUIT OPEN Measure the resistance of the (K977) Mode Select circuit between the Transfer Case Selector Switch harness connector and the Final Drive Control Module C2 harness connector. Is the resistance above 5.0 ohms? Yes Repair the (K977) Mode Select circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  8. 8) 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. While monitoring the scan tool data relative to this circuit, move the selector switch to each position several times. Look for the data to change other than as expected or for the DTC to reset. Were any problems found? Yes Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) T-CASE POSITION SENSOR VOLTAGE BELOW 0.4 VOLTS Ignition on, engine not running. With the scan tool, read the T-Case Position Sensor voltage in the Final Drive Control Module. Is the voltage below 0.4 volts? Yes Go to 2) . No Go to 7) .
  2. 2) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT VOLTAGE 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 (K504) Drivetrain 5-volt Supply circuit. Is the voltage below 0.2 volts? Yes Go to 3) . No Go to 5) .
  3. 3) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT OPEN Turn the ignition off to the lock position Disconnect the Final Drive Control Module C2 harness connector. 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 (K504) Drivetrain 5-volt Supply circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 4) .
  4. 4) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K504) Drivetrain 5-volt Supply circuit. Is the resistance below 5.0 ohms? Yes Repair the (K504) Drivetrain 5-volt Supply circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  5. 5) TRANSFER CASE MOTOR With the scan tool, read the T-Case Position Sensor voltage in the Final Drive Control Module. Is the voltage above 4.5 volts? Yes Replace the Transfer Case Motor in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 6) .
  6. 6) (T313) MODE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (T313) Mode Sensor Signal circuit. Is the resistance below 5.0 ohms? Yes Repair the (T313) Mode Sensor Signal circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  7. 7) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) T-CASE POSITION SENSOR VOLTAGE ABOVE 4.8 VOLTS Ignition on, engine not running. With the scan tool, read the T-Case Position Sensor voltage in the Final Drive Control Module. Is the voltage above 4.8 volts? Yes Go to 2) . No Go to 7) .
  2. 2) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE 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 (K504) Drivetrain 5 Volt Supply circuit. Is the voltage above 5.5 volts? Yes Repair the (K504) Drivetrain 5 Volt Supply circuit for a short to voltage. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) (T313) MODE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE Measure the voltage of the (T313) Mode Sensor Signal circuit. Is the voltage above 5.5 volts? Yes Repair the (T313) Mode Sensor Signal circuit for a short to voltage. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 4) .
  4. 4) TRANSFER CASE MOTOR Turn the ignition off to the lock position Connect a jumper wire between the (K594) Drivetrain Sensor Return circuit and the (T313) Mode Sensor Signal 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. NOTE: Remove the jumper wire before continuing. Is the voltage below 0.2 volts? Yes Replace the Transfer Case Motor in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 5) .
  5. 5) (T313) MODE SENSOR SIGNAL CIRCUIT OPEN Turn the ignition off to the lock position Disconnect the Final Drive Control Module C2 harness connector. 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 (T313) Mode Sensor Signal circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 6) .
  6. 6) (K594) DRIVETRAIN SENSOR RETURN CIRCUIT OPEN 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 above 5.0 ohms? Yes Repair the (K594) Drivetrain Sensor Return circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  7. 7) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE Start the engine and allow it to idle. Move the Transfer Case Selector Switch to each position several times. With the scan tool, read DTCs in the Final Drive Control Module. Is the status Active for this DTC? Yes Go to 2) . No Go to 7) .
  2. 2) (T317) TRANSFER CASE MOTOR LOCK SIGNAL CIRCUIT SHORTED TO GROUND Turn the ignition off to the lock position Disconnect the Transfer Case Motor harness connector. Disconnect the Final Drive Control Module C1 harness connector. Measure the resistance between ground and the (T317) Transfer Case Motor Lock Signal circuit. Is the resistance below 5.0 ohms? Yes Repair the (T317) Transfer Case Motor Lock Signal circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) ACTUATE T-CASE MOTOR SOLENOID LOCK Connect the Final Drive Control Module C1 harness connector. Ignition on, engine not running. Using the scan tool, clear the DTCs in the FDCM. With the scan tool, actuate the T-Case Motor Solenoid Lock in the Final Drive Control Module. Using a 12-volt test light connected to 12-volts, check the (T317) Transfer Case Motor Lock Signal circuit with the circuit actuated. NOTE: Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly with the circuit actuated? Yes Go to 5) . No Go to 4) .
  4. 4) (T317) TRANSFER CASE MOTOR LOCK SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE Turn the ignition off to the lock position Disconnect the Final Drive Control Module C1 connector. Measure the resistance of the (T317) Transfer Case Motor Lock Signal circuit between the Final Drive Control Module C1 harness connector and the Transfer Case Motor harness connector. Is the resistance above 5.0 ohms? Yes Repair the (T317) Transfer Case Motor Lock Signal circuit for an open circuit or high resistance. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  5. 5) (T301) SWITCHED BATTERY SOLENOID SUPPLY VOLTAGE Ignition on, engine not running. Using a 12-volt test light, jumper the (T301) Switched Battery Solenoid Supply circuit to the (T317) Transfer Case Motor Lock Signal in the Transfer Case Motor harness connector. NOTE: As a failsafe precaution when either the Front Differential Solenoid, Rear Differential Solenoid, or the Transfer Case Motor harness connectors are disconnected, the DTCs must be cleared in the FDCM. Failure to follow this will result in the FDCM detecting this condition and turning OFF the Switched Battery Solenoid Supply circuit. Using the scan tool, clear the DTCs in the FDCM. With the scan tool, actuate the T-Case Motor Solenoid Lock in the Final Drive Control Module. NOTE: Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? Yes Replace the Transfer Case Motor in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 6) .
  6. 6) (T301) SWITCHED BATTERY SOLENOID SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE Turn the ignition off to the lock position Disconnect the Final Drive Control Module C1 connector. Measure the resistance of the (T301) Switched Battery Solenoid Supply circuit between the Final Drive Control Module C1 harness connector and the Transfer Case Motor harness connector. Is the resistance above 5.0 ohms? Yes Repair the (T301) Switched Battery Solenoid Supply circuit for an open circuit or high resistance. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  7. 7) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE 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 Go to 2) . No Go to 4) .
  2. 2) TRANSFER CASE INTERNAL CONDITION Turn the ignition off to the lock position Inspect the Transfer Case in accordance with the Service Information to determine if there are any mechanical conditions that are preventing the Shift Motor from engaging the requested range. Are any mechanical conditions preventing the Shift Motor from engaging the requested range? Yes Repair or replace the Transfer Case in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) TRANSFER CASE MOTOR Turn the ignition off to the lock position Using the wiring diagram/schematic as a guide, inspect all wiring and connectors that pertain to this circuit. If any problems are found, repair as necessary and retest. If no other problems are found, replace the Transfer Case Motor in accordance with the Service Information. Ignition on, engine not running. Cycle the Transfer Case Selector Switch to each position several times during a test drive. With the scan tool, read DTCs in the Final Drive Control Module. Is the DTC status Active? Yes Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  4. 4) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) NEUTRAL INDICATOR CONTROL CIRCUIT DTC IS ACTIVE Turn the ignition off to the lock position With the scan tool, read DTCs in the Final Drive Control Module. Is the status Active for this DTC? Yes Go to 2) . No Go to 3) .
  2. 2) TRANSFER CASE SELECTOR SWITCH Turn the ignition off to the lock position Disconnect the Transfer Case Selector Switch. Ignition on, engine not running. With the scan tool, read the 4WD Range Switch Voltage in the Final Drive Control Module. The switch voltage should be approximately 0.0 volts. Turn the ignition off to the lock position Connect a jumper wire between the (K504) Drivetrain 5-volt Supply circuit and the (K977) Mode Select circuit in the Transfer Case Selector Switch connector. Ignition on, engine not running. With the scan tool, read the 4WD Range Switch Voltage in the Final Drive Control Module. The switch voltage should be approximately 5 volts. Does the voltage display as described? Yes Replace the Transfer Case Selector Switch. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  3. 3) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE 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 Go to 2) . No Go to 3) .
  2. 2) TRANSFER CASE SELECTOR SWITCH Turn the ignition off to the lock position Disconnect the Transfer Case Selector Switch. Ignition on, engine not running. With the scan tool, read the 4WD Range Switch Voltage in the Final Drive Control Module. The switch voltage should be approximately 0.0 volts. Turn the ignition off to the lock position Connect a jumper wire between the (K504) Drivetrain 5-volt Supply circuit and the (K977) Mode Select circuit in the Transfer Case Selector Switch connector. Ignition on, engine not running. With the scan tool, read the 4WD Range Switch Voltage in the Final Drive Control Module. The switch voltage should be approximately 5 volts. Does the voltage display as described? Yes Replace the Transfer Case Selector Switch. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  3. 3) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE NOTE: If both DTCs C1415 and C140A are present, check the FDCM fuse and the B(+) supply to the Integrated Power Module (IPM). Ignition on, engine not running. With the scan tool, read DTCs in the Final Drive Control Module. Pick the answer that best describes the DTC set conditions? If DTCs C1415 and C140A are both present, Go to 2) . If DTC C1415 is active, Go to 4) . If DTC C1415 is stored (not active), Go to 5) .
  2. 2) (A909) FUSED B(+) CIRCUIT FOR VOLTAGE Turn the ignition off to the lock position Disconnect the FDCM C1 harness connector. Ignition on, engine not running. Using a 12-volt test light connected to ground, check the (A909) Fused B(+) circuit in the FDCM harness connector. NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? Yes Go to 4) . No Go to 3) .
  3. 3) (A909) FUSED B(+) CIRCUIT FOR AN OPEN Turn the ignition off to the lock position Disconnect the IPM C1 harness connector. Measure the resistance of the (A909) Fused B(+) circuit between the IPM C1 harness connector and the FDCM C1 harness connector. Is the resistance above 5.0 ohms? Yes Repair the (A909) Fused B(+) circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Integrated Power Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  4. 4) TRANSFER CASE MOTOR Turn the ignition off to the lock position Using the wiring diagram/schematic as a guide, inspect all wiring and connectors that pertain to this circuit. If any problems are found, repair as necessary and retest. If no other problems are found, replace the Transfer Case Motor in accordance with the Service Information. Ignition on, engine not running. Cycle the Transfer Case Selector Switch to each position several times during a test drive. With the scan tool, read DTCs in the Final Drive Control Module. Is the DTC status Active? Yes Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  5. 5) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE NOTE: Diagnose and repair any system voltage or Transfer Case related DTCs in the Final Drive Control Module before continuing with this test. Ignition on, engine not running. With the scan tool, clear Stored DTCs in the Final Drive Control Module. Test drive the vehicle. During the test drive, move the Transfer Case Selector Switch to each position several times in accordance with the Service Information. With the scan tool, read DTCs in the Final Drive Control Module. Does this DTC reset? Yes Go to 2) . No Go to 4) .
  2. 2) TRANSFER CASE SELECTOR SWITCH Using the wiring diagram/schematic as a guide, inspect the wiring and connectors relative to this circuit. While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors. Were any problems found? Yes Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) FINAL DRIVE CONTROL MODULE Turn the ignition off to the lock position Replace the Transfer Case Selector Switch in accordance with the Service Information. Ignition on, engine not running. With the scan tool, clear Stored DTCs in the Final Drive Control Module. Test drive the vehicle. During the test drive, move the Transfer Case Selector Switch to each position several times in accordance with the Service Information. With the scan tool, read DTCs in the Final Drive Control Module. Does this DTC reset? Yes Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test Complete. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  4. 4) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) CHARGING SYSTEM DTCS PRESENT Ignition on, engine not running. With the scan tool, read DTCs in the Powertrain Control Module. Are there any Charging System or related voltage DTCs present? Yes Refer to the appropriate symptom list and perform any Charging System DTC diagnostic procedures before continuing with this test. Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article. No Go to 2) .
  2. 2) DTC IS ACTIVE With the scan tool, read DTCs in the Final Drive Control Module. Is the status Active for this DTC? Yes Go to 3) . No Go to 4) .
  3. 3) FINAL DRIVE CONTROL MODULE GROUND CIRCUITS OPEN OR HIGH RESISTANCE Turn the ignition off to the lock position Disconnect the Final Drive Control Module C1 and C2 harness connectors. Ignition on, engine not running. With a 12-volt test light connected to B+, check the Ground circuits in the Final Drive Control Module C1 and C2 harness connectors. NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly for each of the Ground circuits? Yes Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Repair the Ground circuit(s) for an open circuit or high resistance. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  4. 4) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DRIVETRAIN 5 VOLT SUPPLY (REFERENCE) VOLTAGE BELOW 4.8 VOLTS Ignition on, engine not running. With the scan tool, read the Drivetrain 5-volt Supply (Reference) Voltage in the FDCM. Is the voltage below 4.8 volts? Yes Go to 2) . No Go to 5) .
  2. 2) TRANSFER CASE SELECTOR SWITCH Turn the ignition off to the lock position Disconnect the Transfer Case Selector Switch harness connector. Ignition on, engine not running. With the scan tool, monitor the 5 Volt Supply (Reference) Voltage. Is the voltage above 4.75 volts with the Transfer Case Selector Switch harness disconnected? Yes Replace the Transfer Case Selector Switch in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) TRANSFER CASE MOTOR Turn the ignition off to the lock position Disconnect the Transfer Case Motor harness connector. Ignition on, engine not running. With the scan tool, read the 5-volt Supply (Reference) Voltage. Is the voltage above 4.75 volts with the Transfer Case Motor harness disconnected? Yes Replace the Transfer Case Motor in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 4) .
  4. 4) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORT TO GROUND Turn the ignition off to the lock position Disconnect the Final Drive Control Module harness connector. Measure the resistance between ground and the (K504) Drivetrain 5- volt Supply circuit. Is the resistance below 5.0 ohms? Yes Repair the (K504) Drivetrain 5 Volt Supply circuit for a short to ground. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  5. 5) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) 5 VOLT SUPPLY (REFERENCE) VOLTAGE IS ABOVE 5.2 VOLTS Ignition on, engine not running. With the scan tool, read the Drivetrain 5-volt Supply (Reference) Voltage in the FDCM. Is the voltage above 5.2 volts? Yes Go to 2) . No Go to 3) .
  2. 2) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE Turn the ignition off to the lock position Disconnect the Transfer Case Motor harness connector. Disconnect the Final Drive Control Module C2 harness connector. Ignition on, engine not running. Measure the voltage of the (K504) Drivetrain 5 Volt Supply circuit. Is there any voltage present? Yes Repair the (K504) Drivetrain 5 Volt Supply circuit for a short to voltage. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  3. 3) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) DTC IS ACTIVE Ignition on, engine not running. With the scan tool, read DTCs in the FDCM. Is the status Active for this DTC? Yes Go to 2) . No Go to 4) .
  2. 2) (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT OPEN Turn the ignition off to the lock position Disconnect the Transfer Case Motor harness connector. Disconnect the Final Drive Control Module C2 harness connector. 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 (K504) Drivetrain 5-volt Supply circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Go to 3) .
  3. 3) (K594) DRIVETRAIN SENSOR RETURN CIRCUIT OPEN 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 above 5.0 ohms? Yes Repair the (K594) Drivetrain Sensor Return circuit for an open. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  4. 4) 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 Repair as necessary. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete.
  1. 1) FINAL DRIVE CONTROL MODULE NOTE: This DTC may set after updating the controller software. Erase this DTC, cycle the ignition off for 10 seconds and recheck. If this DTC resets, proceed with repair procedure. If it does not reset, repair is complete. The Final Drive Control Module has detected an internal failure. View repair Repair Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) FINAL DRIVE CONTROL MODULE CONFIGURATION The Final Drive Control Module hardware check has determined that module configuration does not match vehicle configuration. Verify that the correct module part number is installed in the vehicle. Turn the ignition on. With the Scan Tool, verify that the VIN stored in the controller matches the vehicle VIN. With the Scan Tool, clear stored DTCs in the Final Drive Control Module. Cycle the ignition off, then on. With the Scan Tool, read DTCs in the Final Drive Control Module. Does this DTC reset? Yes Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Test complete. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) POWERTRAIN DTCS PRESENT Ignition on. With the scan tool, read DTCs in the Powertrain Control Module. Are there any DTCs present? Yes Refer to the appropriate symptom list and perform the applicable diagnostic procedure. Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) TRANSMISSION DTCS PRESENT Ignition on, engine not running. With the scan tool, read DTCs in the Transmission Control Module. Are there any DTCs present? Yes Refer to the appropriate symptom list and perform the applicable diagnostic procedure. Refer to appropriate Transmission ELECTRICAL DIAGNOSTICS article. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) ABS DTCS PRESENT Ignition on, engine not running. With the scan tool, read DTCs in the Antilock Brake Controller. Are there any DTCs present? Yes Refer to the appropriate symptom list and perform the applicable diagnostic procedure. Refer to appropriate ABS - ELECTRICAL DIAGNOSTICS article. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) STEERING COLUMN CONTROL MODULE DTCS PRESENT Ignition on, engine not running. With the scan tool, read DTCs in the Steering Column Control Module. Are there any DTCs present? Yes Refer to the appropriate symptom list and perform the applicable diagnostic procedure. Refer to appropriate Steering ELECTRICAL DIAGNOSIS article. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) FRONT CONTROL MODULE DTCS PRESENT Ignition on, engine not running. With the scan tool, read DTCs in the Front Control Module. Are there any DTCs present? Yes Refer to the appropriate symptom list and perform the applicable diagnostic procedure. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) . No Replace the Final Drive Control Module in accordance with the Service Information. Perform «TRANSFER CASE VERIFICATION TEST»(ref-288319-S22880867112008062000000) .
  1. 1) TRANSFER CASE VERIFICATION TEST- VER 1 Disconnect all jumper wires and reconnect all previously disconnected components and connectors. With the scan tool, select Clear Stored DTCs. Make sure that all accessories are turned off and that the battery is fully charged. Test drive the vehicle in each Transfer Case range and verify proper operation in each range. NOTE: To select or deselect 4LO (if equipped), vehicle speed must be below 3 M.P.H. (5 KM/H) with the ignition ON and the transmission in neutral (auto trans). NOTE: To select or deselect Transfer Case Neutral, vehicle speed must be 0 M.P.H. with the ignition ON, engine OFF, the brake pedal applied, and the transmission in neutral (auto trans). Press the Neutral button (if equipped) on the Transfer Case Selector Switch until the Neutral Indicator is illuminated solidly and the cluster displays '4WD System in Neutral'. WARNING: Apply the parking brake. The vehicle may roll with the Transfer Case in neutral. NOTE: To verify that the Transfer Case is in Neutral, shift the automatic transmission into reverse and release the brake pedal for three seconds. There should be no vehicle movement if the Transfer Case is in Neutral. With the scan tool, select View DTCs in the Final Drive Control Module. Are there any DTCs present in the Final Drive Control Module? Yes Return to the symptom list and perform the appropriate diagnostic test. No Repair is complete.

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