The night before leaving for a work trip my battery/charge malfunction light came on. I told my son he could use the X5 to move while I'm away. Well it died with it loaded. He called AAA and it started and ran while hooked to his cables but died immediately when he disconnected them. Had it towed to the MB dealer where my son works and ordered an OE alternator. He changed it today and after a long drive home my son says it won't start again, it's still dead. The battery is one year old. Any ideas?