I had a 99 for a short time, and determined the fog lights did not work. It seems that the lights did not meet certain state codes and the bulbs were either removed or not installed. They also deactivated the circuit via the AAM (body computer). My dealer would not activate them in FL but my dealer in IL said no problem. I finally told them I was going to install the auxilliary lamps, so the body shop activated them. There are two steps, one is to activate the circuit, and the other to illuminate the indicator on the cluster (in addition to the switch). The later MLs changed the fog lamps to be compliant.