I believe the courtesy lighting feature turns on the fog lamps not the headlights.

On the W202, the foglamps are in the main headlight unit. Maybe your driver's side fog lamp is burned out. The bulbs are below the low beam bulbs in the unit.

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Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record