C140A

C140A- TRANSFER CASE MOTOR PERFORMANCE





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 under-voltage or over-voltage condition present.

- Set Condition:
A faulted condition is detected in the H-bridge driver.





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

Is DTC active?

Yes

- Go To 2

No

- Go To 5

2. (T315) STEP MOTOR CONTROL B CIRCUIT SHORTED TO GROUND




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 resistance between ground and the (T315) Step Motor Control B circuit at the Transfer Case Motor harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Repair the short to ground in the (T315) Shift 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 SHORTED TO GROUND




1. Measure the resistance between ground and the (T316) Step Motor Control C circuit at the Transfer Case Motor harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Repair the short to ground 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 SHORTED TO THE (T316) STEP MOTOR CONTROL C CIRCUIT




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

Is the resistance below 5.0 Ohms?

Yes

- Repair the short between the (T315) Step Motor Control B circuit and the (T316) Step Motor Control C circuit.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test.

No

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

5. INTERMITTENT WIRING 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 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.