I shut off my ac unit a mouth ago. Got up Sunday morning and the fan on the out side unit was running and will not shut off . Every thing is off heat and air. I shut off out side power to unit to get it to shut off. It is a Trane EX1000 Heat Pump. There is a red LED light blinking on the circuit board.

Check to see if the contactor is stuck closed in the outside unit.

Every thing is ran through a printed circuit board. Have one coming tomorrow . Hope that works Thanks

Was the fan running at full speed? Strange that it just started up of it's own will... power wiring on Trane units is a little different than most. I have seen more than a few cases of a shunted compressor causing the fan to run slowly during off-cycles. Once you unpack and install that board, you've bought it for good.