On mye 98 ML320 when the brake/dash light comes on its time for new "front" brake pads.

rear pad woes
 

It seems more and more that ML55's and 430's with fixed rear calipers wear out the rear pads at an alarming rate. I've been told this is from the esp applying the rear brakes first and sometimes only the rear brakes. If you drive a 55 in the snow much you'll hear that poor esp/abs pump clattering away.

1. Are you talking about the yellow brake light?
2. How do you know it's the front pads - the light does not have any indications front or rear?

The manual actually suggests it could a low level of brake fluid. I tried to find it in Checkers but no luck. Any suggestions on where to buy the brake fluid expect the dealeship?