A. Reprogram HVAC Control Head

CAUTION:
All involved vehicles must be reprogrammed before testing the actuators. Failure to reprogram the HVAC control head before testing could result in inaccurate test results.

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. Set the HVAC mode knob to Face (or Bi-level) and blower knob at "Low" setting.

5. Open the wiTECH desktop application.

6. On vehicles equipped with ATC, continue with Step 7 of this procedure. On vehicles equipped with MTC, continue with the procedure below to verify or update the control head bootloader software.

a. Starting at the "Vehicle View" screen, select "HVAC"

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

c. Read the "Current ECU Flash Number

> If the part number is 55056826AE, 55056826AF, 55056829AE or 55056829AF, reprogram the bootloader choosing the updated software from the list on the wiTECH screen. After reprogramming is complete, continue with Step 7 of this procedure.

NOTE:
After reprogramming the bootloader, restart the wiTECH application to refresh the wiTECH system before continuing with Step 7.

> If the part number is ANY other than 55056826AE, 55056826AF, 55056829AE or 55056829AF , the bootloader does not require reprogramming Continue with Step 7 of this procedure.

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

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

9. Select the software update from the list.

10. Follow the screen prompts to complete the reprogramming process.

11. Clear all Diagnostic Trouble Codes (DTC's).

NOTE:
Disregard DTC B2214 (HVAC) "Climate Control Internal" if it appears in active or stored state. Do not replace the HVAC control head.

12. Continue with Section B. Actuator Test.