The BAS/ETS/ABS lights illuminated on my 2002 ML320. Since nothing seemed wrong, the driver kept running errands for the next few hours. When the car returned home, there was a noise from left front of engine compartment that sounded like a bad bearing or burnt out pump. Noise continued after the engine was turned off. Pulling the ABS pump relay (K25) stopped the noise, and replacing it (with a new one) a few minutes later resulted in the dash lights going off, no more noise, all's fixed.

Question: the root problem was obviously the stuck relay, but the noise concerns me. Would the stuck relay (for several hours, at least) have damaged something, maybe a pump that I won't know is damaged until I need ABS?! Or just temporary overheating? Any diagnostics I should do?

Thanks.