AC blinking
 

Hi
I have problem with AC of my 2007 Lexus IS300 , it is blinking , when it blink it become hot and seem to be only the fan is working , so i have to press again to resume it again , this happen many times within less than 1 hour .
I checked it on a computer and these two errors (b1424-b1421 solar sensor circuit ) appears. Please let me know what to do ?
thanks