W203 A/C problem

[rrf]

Hello A/C gurus

New 2002 W203 C-Class Sedan, but same scenario as Mr. Raygun17

AC = Hot air output when hot outside (80-90 degrees actual air temp), and idling/sitting.
AC = Works fine when in shade, running on freeway etc.
AC after running and then parking in the sun, takes forever to come back into cool air mode.

There is a A/C diagnostic mode one can enter into on the front of unit, all looks OK (to me) except the register for "Outside Air Temp", It reads in the 69-84 range when OK and gets into the 120-165 range when the AC is blowing hot air.

Do you think the Recirc Flap is likely? where is it actually located and how to easily test it?

FYI Excel spreadsheet of Diagnostic Mode, attached