the car is a c200 w202 1997 .

the little yellow bulb blown warning light comes on when i switch on the dipped headlamps.

all the exterior bulbs including brake light,reverse light, rear fogs,number plate lamps,rear lights,front parking lights,dipped lamps,fog lights and main beam are working ok-so why am i get the warning light on the dash?

this is a mystery and any help is appreciated.