212 estate rear parking sensors

[borntobemild]

Hi all,

Recently bought a 2010 e350 cdi blueefficiency sport estate. Its a fantastic vehicle but it came with a small problem. The rear O/S had had a little bump which just about crazed the paintwork but did not crack the bumper. When selecting reverse the 4 red lights showed the rear parking sensors had a malfunction. I checked with my iCarsoft scanner and it showed number 7 sensor had a open circuit. I ordered a replacement part A2125420018 which happened to be a Bosch sensor which was an exact replacement for the faulty one. Apart form a real problem .removing the bumper because some numpty had glued it back in place instead of changing a broken bracket, I replace the sensor and still have the 4 red lights. The error code has changed to malfunction wrong component installed. Anyone throw any light on this message as the sensor is the correct part number as far as I can see. I understand all the 4 sensors are identical on the rear. Appreciate any help from y'all.

 

[FiveAlive]

Where did you get the sensor? The part number is correct for all of the rear sensors and the front-facing sensors on the front bumper, but it might be worth checking that they didn't give you a A2125420118 by mistake - that's the sensor for the side-facing sensors on the front bumper.

 

[borntobemild]

Definitely an A2125420018 sensor. My vehicle only has 4 front sensors and 4 rear and all are the same. Can't understand why the error message changed when this sensor was installed but still getting 4 read lights and beep.