C1438-TRANSFER CASE DIFFERENTIAL CLUTCH WORN
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
The ignition on, engine running. No Under/Overvoltage, and/or encoder error DTCs present. When shifted into 4-Low or in 4-high.
- Set Condition:
The Final Drive Control Module is unable to fully lock the T-Case (in Either High or Low) because the T-Case clutch is worn.
| Possible Causes |
| (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE |
| (T313) MODE SENSOR SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE |
| (K594) DRIVETRAIN SENSOR RETURN CIRCUIT OPEN OR HIGH RESISTANCE |
| TRANSFER CASE CLUTCH WORN |
| FINAL DRIVE CONTROL MODULE (FDCM) |
Diagnostic Test
1. DTC IS ACTIVENOTE: Diagnose and repair any system voltage or Transfer Case related DTCs in the FDCM before continuing with this test.
Ignition on, engine 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 7
2. TRANSFER CASE POSITION SENSOR VOLTAGE
Turn the ignition off to the lock position.
Disconnect the Transfer Case Motor harness connector.
Connect a jumper wire between the (T313) Mode Sensor Signal circuit and the (K594) Drivetrain Sensor Return circuit.
Ignition on, engine running.
With the scan tool, read the T-Case Position Sensor voltage.
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 in accordance with the Service Information.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Go to 3
3. TRANSFER CASE POSITION SENSOR VOLTAGE
Turn the ignition off to the lock position.
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.
Ignition on, engine running.
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 the Transfer Case in accordance with the Service Information.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Go to 4
4. (K504) DRIVETRAIN 5 VOLT SUPPLY CIRCUIT HIGH RESISTANCE
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 high resistance in the (K504) Drivetrain 5 Volt Supply circuit.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Go to 5
5. (T313) MODE SENSOR SIGNAL CIRCUIT HIGH RESISTANCE
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 high resistance in the (T313) Mode Sensor Signal circuit.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Go to 6
6. (K594) DRIVETRAIN SENSOR RETURN CIRCUIT HIGH RESISTANCE
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 in accordance with the Service Information.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Repair the high resistance in the (K594) Drivetrain Sensor Return circuit.
- Perform the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
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 the TRANSFER CASE VERIFICATION TEST-VER 1 (Refer to 21 - TRANSMISSION/TRANSAXLE/TRANSFER CASE - STANDARD PROCEDURE).
No
- Test complete.