A. Check HVAC Control Head Module Status

1. Open the hood. Install a battery charger and verify that the charging rate provides 13.0 to 13.5 volts. Do not allow the charger to time out during the flash process. Set the battery charger timer (if so equipped) to continuous charge.

2. Connect the StarMOBILE scan tool to the vehicle data link connector located under the steering column and place the ignition in the "RUN" position.

3. Power "ON" the StarMOBILE scan tool and open StarMOBILE Desktop Client.

4. Starting at the "Home" screen select "ECU View".

5. Select "HVAC Heat, Ventilation and A/C" from the list.

6. Select "More Options".

7. Select "ECU Details".

8. Check the HVAC control head part number:

> If the part number displayed is 55056826AG, 55056829AG, 55111309AA or 55111310AA no further action is required. Disconnect and remove the scan tool, battery charger and return the vehicle to the customer.

> If the part number displayed is 55056826AE, 55056826AF, 55056829AE or 55056829AF continue with Section C. Reprogram the HVAC Control Head Module using StarMOBILE.

> If the part number displayed is ????????? (all question marks), continue with Section D. Replace the HVAC Control Head Module.

Using wiTECH:

1. Open the hood. Install a battery charger and verify that the charging rate provides 13.0 to 13.5 volts. Do not allow the charger to time out during the flash process. Set the battery charger timer (if so equipped) to continuous charge.

2. Connect the wiTECH pod to the vehicle data link connector located under the steering column.

3. Place the ignition in the "RUN" position.

4. Open the wiTECH desktop application.

5. Starting at the "Vehicle View" screen, select "HVAC" from the modules on the "Vehicle View" screen illustration.

6. Select the "Flash" tab at the top of the screen.

7. Read the HVAC control head module part number.

> If the part number is 55056826AG, 55056829AG, 55111309AA or 55111310AA no further action is required. Disconnect and remove the scan tool, battery charger and return the vehicle to the customer.

> If the part number is 55056826AE, 55056826AF, 55056829AE or 55056829AF continue with Section B. - Reprogram the HVAC Control Head Module using wiTech.

> If the screen displays "Invalid Part Number" continue with Section D. - Replace the HVAC Control Head Module.