190E ABS light on & battery dies - help!

[lore]

A few weeks ago, my car (1991 190E 2.3) died at a stoplight and the battery appeared to be dead. I replaced the battery and alternator with a reman. The car ran fine until a few days ago, when the ABS light came on and the car eventually stalled (battery dead again).

The ABS light came on several minutes before the battery died, leading me to believe that the OVP relay might be part of the problem. My SRS light is out, so I'm not sure what it was doing during this time.

Saturday, I replaced the OVP relay. All symptoms remain the same - car starts fine with a jump, unplug the jumper cables and the ABS light comes on (low charging voltage?) and the engine eventually dies. I'm guessing that the alternator might be bad again, and my next step is to head out with a multimeter and measure the voltage. Is there anything else for which I should check? Thanks in advance.