How to conduct an A/C reset?

If the A/C was running when the vehicle overheated, it is possible that the pressure relief valve blew and released refrigerant. You can look on the rear of the compressor and see if there is any greenish, oily residue.
But here is the recalibration procedure for the HVAC unit.

1. Turn the ignition switch to the on position.
2. If equipped with the manual temperature control (MTC) system, press and hold the Rear Wipe/ Wash and Recirculation buttons for at least five seconds. If equipped with the automatic temperature control (ATC) system, simultaneously press and hold the Power and Recirculation buttons on the A/Cheater control for at least five seconds. The MTC A/C-heater control Rear Wipe/Wash button light emitting diode (LED) and Recirculation button LED, or the ATC A/C-heater control Delay and Recirculation graphics will begin to flash when the calibration procedure has begun.
3. The calibration procedure should take less than two minutes to complete for the manual A/C-heater control, and less than twenty seconds for the ATC A/C-heater control. When the LEDs or graphics stop flashing, the calibration procedure is complete.
4. If the LEDs or graphics continue to flash beyond the two-minute (manual) or twenty second (ATC) calibration time, it indicates that the A/Cheater control has detected a failure and a Diagnostic Trouble Code (DTC) has been set. The LEDs or graphics will continue to flash even after the ignition switch is cycled Off and On, until a successful calibration is completed or until the vehicle has been driven about 13 kilometers (8 miles).

Please let me know if this helps.