I just bought a compatible O2 sensor for my car (BOSCH one, identical to the one I've got on the car but with a different electrical plug because it belongs to a different car model), I am going to re-wire it to put on it the original MB connector.

It's a 3 wires: 2 whites and one black.

I am assuming the 2 whites are for the heater, so without polarity and the black one for the signal?

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From 300CE to SLK230K