When does the warning illuminate?
-- When turning on parking lights (one click to right)
-- When turning on headlights (two clicks to right)
-- When pressing on brake
-- When using turn signals
That will help you to know which bulbs to check. You may have to remove each bulb in turn, checking for corrosion of the base or the socket, loose connections, disconnected filaments, etc.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970