No Response and unable to reset

Hi

My Time Capsule currently not working probably, the light turn to yellow, no wifi signal, unable to connect the AirPort drive and unable to reboot or reset.

This happened the second time this year, the problem found last time I bought to repair but extremely expensive. And the same problem came with out again, does anyone got idea how to fix it (at least I want all my files back)

Many Thanks

Christopher