abs light, weird buzzing noise, dead!

[johnp352]

94 E 420 105K. running fine, though lately it takes a second crank to start from overnight cold. Car ran fine all day. On last run of the day, ABS light comes on from the start , accompanied by strange buzzer/warning sound I have never heard before..the sound itself sounded like there was an intermitent in the buzzer. Pull off into a parking lot, shut off car. Tried to start car, wouldn't turn over. Battery appears good, all lights, etc work. Had car jumped by AAA, nothing. Towed to Merc dealer, where the car sits this morning.

There's no OVP as far as I can tell by reading this forum, in 90's V-8's? What is going on?