K-x mirror stuck ?

Hi guys,
Just got a K-x problem come in from the daughter.
She said it sounded like the shutter sound was interrupted then all went black. No nothing. Tried batteries and card.
Told her to look in the front. She reckons its just black in there too no mirror at 45degrees or sensor.
I thought those were the only two choices

Presumably if something is stuck, the camera would default to off ?
sorry about lack of detail. All this via txt
First I've heard of the issue.
Of course i bought it second hand for her so the warranty is moot.
Pete

First step with any electronic device - try taking the batteries out and leaving it for a few hours until any residual charge has dissipated, then reinsert known good batteries. If that doesn't cure it I think you're looking at talking to Pentax Service.

Thanks Dangermouse.
It recovered the next day, must have been an April thing .
cheers
Pete