vauxhall combo van 2007 radio not working?

hi just bought a 53 plate vauxhall combi van but the radio wont come on as in pressing the round button the acts as the volume button to.
Just says share on display ? any ideas

Jay
June 2016

Hello, i repaired one of these today, after following loom from stero thru bulkhead thru fusebox found independant fuse behind battery that was heavly corroded, cleaned up and greased now working lovely, this would give you low voltage reading at stero if load is applied and proberly battery voltage if stereo was dissconnected. Hth dazzle

Daz saunders
January 2012