If it is the wear sensors then you will certainly have to change at least one of the sensor wires as it will have ground out the insulation to earth the lite on. Makes sense to change the lot and as rightly said, usually the pads come with a set anyhow. good luck !

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1993 190E 2.0L (Euro.) sold
1991. 500 SEL (Euro.)
1991. 300 CE (Euro.) sold
1993. 500 E (U.S. spec.)