I am the original owner of a 1999 Odyssey with 78,000 miles. Yesterday, I was only getting warm air from the air conditioner.
Playing with the different buttons, the cool air came on an stayed on all day.
At night, the warm air returned and all of the display lights on the climate control panel were not illuminated.
I'm sure that there are probably several causes of this problem but I hate to be at the mercy of a repair shop who could tell me that major repairs are necessary.
Any thoughts would be appreciated.

. Check all under dash and under hood fuses with a test light or multimeter.

. Focus on the blend door actuator, which controls the amount of hot and cold air.