in the fuse box there is a long relay that is called the bulb monitor relay.all the power to the light bulbs[external]goes thru this relay it is your most probable culprit.this is the relay that illuminates the bulb out icon in the instrument panel.

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David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
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