If the 116's are anything like 123's and 126's it is probably your brake pad warning lite. Tells you when the pads are worn down and need to be replaced. Gets its signal from small wires that end in small probes that are poked into little factory drilled holes in the front brake pads.

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1961 190Db retired
1968 220D/8 325,000
1983 300D 164,150