C238 E400 2017 model - parking sensor faulty

anyweb

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hiya,
one of my front sensors has developed a fault, I cannot see any damage to it (no scratches, not loose etc) in that when its raining (like now) when i'm at low speed it's always thinking something is directly infront of it so it shows up as red in my 360 view and beeps, i can turn it off but i'd like to replace it,
is it hard to replace and how exactly do I go about doing that,
strangely when it's dry weather it has no issues and performs like normal, it's the sensor just to the lower right of the front number plate

cheers
niall
 
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anyweb

anyweb

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oh and when i say i'd like to replace it, i mean i'd like to fix it, so if i can fix it easily then please suggest the way,
it sounds to me like some wire is shorting or something and when wet it makes a connection and therefore beeps,

surely someone here has gone through something similar ?
 

alexanderfoti

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Unfortunately, a common failure mode of these sensors. They often behave as you say, when wet, progressing to 2 red dots constantly. It's almost certainly a failed sensor.

Swapping it our isn't too hard, but sometimes the bumper has to be unclipped and pulled away from the bumper support to access the sensors.
 
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anyweb

anyweb

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thanks Alex
do you by any chance know which sensor part number I should replace with ?
 

alexanderfoti

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Unfortunately, there are two part numbers. The ones on the end of the bumper facing to the side are different (they are used for parking assist), so you need to identify which is giving issues first.
 

mioba

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Hej,
if you know which sensor it is then ask your dealer. Sensors per se are easy to replace (just held in by clips) bumper and plug.
Its the access and hoping the clips are mud free which is the hard part.
If caked in mud / old debris a good hosing down first is needed.
 
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anyweb

anyweb

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ok does this tell you which sensor it is Alex ? it is literally positioned bottom left of the number plate if you are looking at the car infront of you, as you can see from the camera shot there's nothing infront of the car, yet there it is doing it's thing (it was damp, I rinsed the car previously)
IMG_1804.jpg
 

alexanderfoti

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Yes that's the inner right sensor. I'll check on epc tomorrow.
 
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