(Solved) Mercedes W205 C220 front parking sensors not working


Solutions of how to solve Mercedes W205 C220 front parking sensors not working
Car model: Mercedes W205 C220 Bluetec Sport
Symptom: front parking sensors have not been working
 Story:
This morning I removed my front bumper and checked everything was connected, I then disconnected the wiring harness and re-connected.
I put the car into ignition 1, and the sensors were working..
I put the bumper back on the car and the started the engine and the parking sensors stopped working again..
it doesn’t look like an issue with individual parking sensors as far as I am aware as they were all ticking..
 
Suggestions:
Suggestion 1. 
There is a diagnostic and "re-calibration" tool in Xentry MB shop tool... you may need to turn this issue over to a dealer or a well-equipped indie...
 
Suggestion 2.
The first question I would ask is: What do you mean by "parking sensors stopped working"? Did you get an error message? How did you determine they are not working?
When I replaced my front grille, I first disconnected the battery and then disconnected the only wiring harness which is on the passenger side corner of the front bumper.
You can actually access that connector easily by turning the right wheel inward and removing the 3 plastic rivets in the inside fender.
Maybe recheck that its connected properly, it has a clip that needs to be in the locked position.
 
(Solved) Mercedes W205 C220 front parking sensors not working
 
Solutions:
Solved finally, replaced the wiring harness and I’m all good to go!
 FYI, Reason I realized parking sensors are not working is because when I put the car in reverse or drive, the sensors just beep with 4 red, and just turns them all off,
the rear sensors give a ticking noise, front does not.
Hope it helps.
 
Thanks.