2001 CLK200 (W208) 80K. Car has been running fine. Car ran fine all day. On last run of the day, ESP and BAS malfunction light comes during journey, accompanied by strange buzzer/warning sound I have never heard before, the sound itself sounded like an intermittent buzzer. This was followed by the ABS Malfunction light and then the Battery/Alternator Malfunction light Vist Workshop. Began to lose power to the engine and revs increased with no power output. Pulled off into a car park, shut off car. Tried to start car, wouldn't turn over. Battery appears good, all lights, windows and radio etc work. Had car jumped which started car but battery not holding charge. Towed to storage until I call tomorrow. Any ideas what might be wrong?