Mercedes Repair Questions? Ask a Mechanic for Answers ASAP
This could be a problem with one or more of the wires going to the sensor or it could be the connector itself that plugs into the sensor, I would take a small pick and see if you can make the connector pins fit tighter and then see if it works better, also be looking for a bad spot in the wiring. You can try stabilizing the wire to locate a problem by tying the wire to something solid near where the wire runs. If all else fails you can try to find a wiring pigtail and splice that in to see if it fixes the problem.