C1407

C1407-TRANSFER CASE BRAKE CONTROL CIRCUIT LOW







- When Monitored:
With the ignition on and no system undervoltage or overvoltage condition present.

- Set Condition:
The Final Drive Control Module (FDCM) detects that the Transfer Case Motor Lock circuit diagnostic input is low when output is off.





1. DTC IS ACTIVE
1. Turn the ignition off to the lock position
2. With the scan tool, record and erase DTCs.
3. Start the engine and allow it to idle.
4. With the scan tool, read DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Go To 4

2. (T301) SWITCHED BATTERY SOLENOID SUPPLY CIRCUIT SHORTED TO GROUND




1. Turn the ignition off to the lock position
2. Disconnect the Transfer Case Motor harness connector.
3. Disconnect the FDCM C1 harness connector.
4. Measure the resistance between ground and the (T301) Switched Battery Solenoid Supply circuit.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (T301) Switched Battery Solenoid Supply circuit for a short to ground.
- Perform the TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test.

No

- Go To 3

3. (T301) SWITCHED BATTERY SOLENOID SUPPLY VOLTAGE




1. Ignition on, engine not running.
2. Connect a 12-volt test light across the (T301) Switched Battery Solenoid Supply circuit and the (T317) Transfer Case Motor Lock Signal in the Transfer Case Motor harness connector.

NOTE: As a failsafe precaution when either 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.

3. Using the scan tool, erase DTCs.
4. With the scan tool, actuate the T-Case Motor Solenoid Lock in the FDCM.

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

No

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

4. 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.
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

- Repair as necessary.
- Perform the TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test.

No

- Test complete.