2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 909

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 909

Circuit/System Testing

Note: When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 - Kit.

Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.

1. Verify that the TRANS IGN1 fuse, underhood fuse block, is not open.

瀚慖f the TRANS IGN1 fuse is open, test the Ignition 1 voltage circuit, front drive axle actuator harness X1 pin C, for a short to ground.

2. Wheels blocked. Parking brake engaged. Transmission in Neutral.

3. Ignition ON, engine OFF. Install a scan tool.

4. Disconnect the X1 harness connector at the front drive axle actuator (FDAA).

5. Using the GY probe J 35616-2A, test for B+ (+0.0/-1.0 V) between the Ignition 1 voltage circuit, FDAA X1 harness pin C, and a good

ground.

瀚慖f the voltage is less than the specified value, test the affected circuit for an open/high resistance or short to ground. If all circuits and

connections test normal, test the TCCM for proper operation.

6. Using the GY probe J 35616-2A, test for B+ (+0.0/-1.0 V) between the Ignition 1 voltage circuit, FDAA X1 harness pin C, and the ground

circuit, FDAA X1 harness pin E.

瀚慖f the voltage is less than the specified value, test the ground circuit for an open/high resistance or short to voltage. If all circuits and

connections test normal, test the TCCM for proper operation.

7. Using the GY probes J 35616-2A, test for B+ (+0.0/-1.0 V) between the Ignition 1 voltage circuit, FDAA X1 harness pin C and the axle

switch signal circuit, FDAA X1 harness pin A.

瀚慖f the voltage is less than the specified value, test the axle switch signal circuit for an open/high resistance, short to ground or short to

voltage. If all circuits and connections test normal, test the TCCM for proper operation.

8. Using the GY probes J 35616-2A, measure the voltage between the front axle actuator control circuit, FDAA X1 harness pin B and a good

ground, while commanding the front axle actuator ON and OFF using the Front Axle Actuator function of the Special Functions feature of

the scan tool. When commanded to ON the voltage should read 0.0 V. When commanded to OFF the voltage should read 3.5-6.0 V.

瀚慖f the measured voltage is less than 3.5 V when commanded OFF, test the front axle actuator control circuit for an open/high resistance or

short to ground. If all circuits and connections test normal, test the TCCM for proper operation.

瀚慖f the measured voltage is greater than 6.0 V when commanded ON, test the front axle actuator control circuit for a short to voltage. If all

circuits and connections test normal, test the TCCM for proper operation.

9. Go to Front Drive Axle Actuator (FDAA) in Component Testing.

Component Testing

Front Drive Axle Actuator (FDAA)

1. Key OFF. Disconnect the X1 connector at the FDAA.

2. Remove the FDAA.

3. Connect the FDAA X1 connector. Position the FDAA so that it is visible from the side of the vehicle.

4. Using the Engage Front Axle function of the Special Function feature of the scan tool, command the front axle ON and OFF. When

commanded ON the plunger on the FDAA should extend. When commanded OFF the plunger should retract.

瀚慖f the FDAA does not perform as described, replace the FDAA.

5. Refer to Front Axle Will Not Engage (See: Transmission and Drivetrain/Transfer Case/Testing and Inspection/Symptom Related Diagnostic

Procedures/MP 3023/3024-NQH - Transfer Case/Front Axle Will Not Engage) or Front Axle Will Not Disengage (See: Transmission and

Drivetrain/Transfer Case/Testing and Inspection/Symptom Related Diagnostic Procedures/MP 3023/3024-NQH - Transfer Case/Front Axle

Will Not Disengage).

Transfer Case Shift Control Module (TCCM)

Note: TCCM's need to be programmed when replaced. If after programming the TCCM comes back as "NO COMM", try reprogramming

again. (Internet/vehicle bandwidth load may cause the programming activity to fail.)

1. Key OFF. Disconnect the X1 connector at the front differential lock actuator (FDAA).

2. Key ON (Ignition C), engine OFF. Install a scan tool.

Note: When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 - Kit.

Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.

3. Using the GY probes J 35616-2A, connect a test light between the Ignition 1 voltage circuit, FDAA X1 harness pin C and the front axle