C140D

C140D- TRANSFER CASE MOTOR CONTROL CIRCUIT OPEN





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.

Theory of Operation
The MP3010 is a one speed On Demand Electro-Mechanical Transfer Case. Torque is always sent to the rear axle but can be varied to the front axle from 0 to 100% depending on the situation. Under normal driving conditions the torque is split 47/53% front to rear. This split is varied based on but not limited to the following inputs: steering angle, driveline torque, wheel slip and vehicle speed. As steering angle increases the amount of torque sent to the front axle is decreased to prevent binding with a minimum split of 0/100. If a slip event is detected with high steering angle the transfer case will activate the clutch to stop the slip. During Regan braking the split is 50/50% front to rear above 30 km/h (19 mph) regardless of steering angle. Below 30 km/h (19 mph) the split modified by steering angle to a minimum of 10/90% to prevent binding but maintain vehicle stability.
- When Monitored:
With the ignition on and no system under-voltage or over-voltage condition present.

- Set Condition:
The Final Drive Control Module (FDCM) detects an open circuit on one of the Transfer Case Step Motor Control circuits.





WARNING: On vehicles equipped with the high voltage system, you must thoroughly read and follow all High Voltage Safety procedures. In addition, before performing any diagnostic or service procedure near a high voltage component, you must perform the High Voltage Power Down. Failure to follow these instructions may result in possible serious or fatal injury

1. DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, read DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Go To 7

2. (T315) STEP MOTOR CONTROL B CIRCUIT OPEN




1. Turn the ignition off to the lock position
2. Disconnect the Transfer Case Motor harness connector.
3. Disconnect the FDCM C2 harness connector.
4. Measure the resistance of the (T315) Step Motor Control B circuit from the Transfer Case Motor harness connector to the FDCM C2 harness connector.

Is the resistance above 5.0 Ohms?

Yes

- Repair then open in the (T315) Step Motor Control B circuit.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

- Go To 3

3. (T316) STEP MOTOR CONTROL C CIRCUIT OPEN




1. Measure the resistance of the (T316) Step Motor Control C circuit from the Transfer Case Motor harness connector to the FDCM C2 harness connector.

Is the resistance above 5.0 Ohms?

Yes

- Repair the open in the (T316) Step Motor Control C circuit.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

- Go To 4

4. (T315) STEP MOTOR CONTROL B CIRCUIT VOLTAGE




1. Ignition on, engine off.
2. Measure the voltage of the (T315) Step Motor Control B circuit at the Transfer Case Motor harness connector.

Is the voltage above 0.5 volts?

Yes

- Repair the (T315) Step Motor Control B circuit for a short to voltage.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

- Go To 5

5. (T316) STEP MOTOR CONTROL C CIRCUIT VOLTAGE




1. Measure the voltage of the (T316) Step Motor Control C circuit at the Transfer Case Motor harness connector.

Is the voltage above 0.5 volts?

Yes

- Repair the (T316) Step Motor Control C circuit for a short to voltage.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

- Go To 6

6. TRANSFER CASE MOTOR




1. Reconnect the Transfer Case Motor harness connector.
2. Measure the resistance between the (T315) Step Motor Control B circuit and the (T316) Step Motor Control C circuit at the FDCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Replace the Final Drive Control Module (FDCM).
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

- Replace the Transfer Case Motor.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

7. INTERMITTENT WIRING HARNESS AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
3. Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
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 TEST Transfer Case Verification Test.

No

- Test complete.