Trouble light is steady flashing. Heat works air doesn't unit out side works fan works on everything except in AC. Help Please

It has a trouble code on the ignition control unit ( next to the flashing red light )

There is a trouble code list on the control box near the red blinking light. I have had the same problem with blinking light. I was having " problems " with pressure switch . HVAC tech came out today said it is the control box is bad, and these white rodgers are junk, and supposedly white rodgers never made them any better