Schematic Reference: Transfer Case Control Schematics

Connector End View Reference: Transfer Case Control Connector End Views

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

1. Turn the ignition ON, with the engine OFF.
2. Ensure that the vehicle is in 4WD mode.
3. Install a scan tool.
4. Using the scan tool, observe the Front Axle Switch parameter.

Does the scan tool display the Front Axle Switch status as Locked?

Go to Step 3

Go to Front Axle Will Not Engage

3

1. Change the transfer case mode from 4WD to AWD mode.
2. Use the scan tool in order to observe the Front Axle Switch parameter.

Does the scan tool display the Front Axle Switch status as Locked?

Go to Step 4

Go to Step 6

4

1. Change the transfer case mode back to 4WD mode.
2. Drive the vehicle for a short test drive while observing the Front and Rear Propshaft Speed parameters.
3. Note the values of the Front and Rear Propshaft Speed parameters at a set speed.
4. Compare the Front and Rear Propshaft Speed parameter values previously noted at the same speeds.

Are the RPM values approximately equal at the same speeds?

Go to Step 6

Go to Step 5

Inspect the front axle and transfer case for a mechanical malfunction. Repair or replace components as needed.

Did you complete the repair?

Go to Step 7

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Replace the transfer case shift control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

Go to Step 7

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1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle in order to determine if the symptom has been corrected.

Is the symptom still present?

Go to Step 2

System OK