Bulb out warning light

On my '92 300D occasionally upon braking the burned out bulb indicator light activates. I've had someone else hold the brake while I look for this phantom bulb to no avail. Today it did it and on a whim, turned on my
headlights. Voila, the indicator went out. What's up?
TIA
JD
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Change out the three brake light bulbs one at a time. You must use German bulb... American bulb with brass base is wrong for MB.
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..... learning all the time here. I have noticed in the past that the brass base bulbs do tend to corrode/oxidize quickly compared to the nickel coated bases... thanks for that Tiger
cheers
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The American and German bulbs have slightly different wattage (resistance). The American draws a little bit more current which may damage the delicate German electronic over long period.
Also, the way to monitor the bulb-out is by comparing the current usage, either to a predefined value or left to right (depending on manufacturer design). So different bulbs on the left and right may trigger the bulb-out warning. On the other hand, no bulb-out warning in the left-right method when BOTH are out.
I suspect JD's problem is on the tail lights. One of the bulb may have a partial short (which changes the current) to the ground (for example, crossing filament). When the taillights are on, diagram is corrected and the current becomes normal.
Tiger wrote:

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