I have a Nordyne 12 seer heat pump, I heard a pop today, and the ac cut off and the thermostat went dark

Jumper red to green, did anything happen?

No

Did you mean in the thermostat box

Did you mean in the thermostat box

Yes at the thermostat

Nothing happened, any other suggestions

You might have/probably blown the transformer

They don`t go bad very often, something maybe a short caused it