Amp Err

Question

hii have Model " VSX-D859TX pioneer " which has the problem when turn on only standy comes up but when push button of turn on the display doesnot come and after 1miute more or less the display comes and shows amp err.after few second the same display flashes then amp shut down.i donot know what happened with the amp. can any one confirm how this shall vanish and what is problem with the amp.thanks Noshad