Hyundai Repair: 2001 XG300 Heater Control, ambient temp, xg300

Question
How do I change the temp indicator on the 2001 XG300's heater controls from Fahrenheit to Celsius?  The instructions as explained in the Owner's Manual (Hold down the Ambient Temp button and Temp control for 3 seconds) don't seem to work.

Answer
The method you indicate is the only way I'm aware of to switch between Fahrenheit and Celsius.  Push in and hold the ambient temperature button.  Then, while holding the ambient temp button in, also press in and hold the cooler temperature button.  After a few seconds the display should switch over.  If not, there is a problem with your control head.