My powersteer gone, my parameter meter shown 0, RPM 0, fuel also 0,

No engine warning light etc. But still can start the engine ( maybe still got battery) still can drive, still got radio, headlight, aircon....
Workshop Mechanic checking fuse, wiring and they changed recon alternator.
Everything back to normal but while driving home, back to square one.
how to know alternator faulty? I had volt meter, is show 10 volt and the engine still running, normally 14 volt.

battery changed 1 mth ago.

Very sad... Pls help urgently...