I'e been called out to a Carrier Puron Ducted system that the internal fan starts and then stops after 10 secs with no error codes on the display. I've set it just for fan only but the result is the same. When the fan starts it seems perfectly fine and powerful. jut not for very ling. The unit would be about 15 years old going off the property but unfortunately the model number can't be read on the outside due to Sun bleaching. The internal unit circuit board can't be accessed as some genius has fitted it up to a wall so I can;t even get the cover off. My main question is :- will the error be indicated on some leds on the main circuit board?