I've done the searches, and it looks like the brake pedal switch is the most common cause of the BAS light coming on the dash. But I'd appreciate a few opinions as a newbie to Benz. I've put about 2000 miles on this car, which has a total around 174,250. The number 2 glow plug is bad, and I haven't gotten around to replacing it yet, but the car has been running fine aside from that MIL.

Tonight, the ASR light came on. As soon as I hit clear to get the dash back to normal, the BAS light came on. After reading about possible problems (such as low voltage), I went out for another drive. My OBD-II scanner shows no code for this -- perhaps because the scanner is too cheap, or perhaps because the BAS/ASR light is not engine related. I have no idea.

The brake lights still work, both when the light is glowing and when it is not. The light resets when I turn off the car and restart, but it seems to be coming back on consistently during driving. However, there is no correlation to it coming on when I brake -- sometimes I'm braking and sometimes I'm not, but either way the light comes on. That makes me think it's not the switch, but...maybe it's stuck?

I read that low voltage may cause this also. In diagnostic mode (using the climate controls), I get a steady 13.5 volts, plus or minus .2 while driving. When the car is off, before ignition, the battery reads out about 11.5 volts while the glowplugs heat. During cranking, voltage dips for a split second to about 8.5 volts, then rebounds almost instantly to 13.5 as the engine starts. Starting is no problem.

So...anyone want to give me some tips? I know my way around cars but am new to Benz, and am not anxious to pay the labor rates that people seem to put on these cars!

Many thanks --
Cheers, John