Front Parking Sensor Issue W205

[Dave60]

Hi all, any help would be appreciated.
Sensors not functioning. I get the 2 red lights on the dash for approx 3 seconds with a bleep for the same. The Parking sensor switch on the centre consule stays red throughout.
I checked the the sensors using a stethoscope and the front inner l/h/s by the number plate isn't working. I've removed the bumper and replaced the sensor with a new one, it was still inoperative. I then swapped the one next to it out (Same sensor) and still the problem exists.
So clearly it can't be the sensor.
Anyone got any ideas.
Cheers
Dave

 

[OneForTheRoad]

Try plugging the non working sensor into another loom plug and see if it still won't work. If it does work, then suspect a break in the loom where it doesn't.

 

[Jobsworth]

Bumper looms on these and w213 are troublesome in my experience. Wires go green inside the insulation. New ones aren’t as expensive as you might expect

 

[Dave60]

Try plugging the non working sensor into another loom plug and see if it still won't work. If it does work, then suspect a break in the loom where it doesn't.

Hi
Thanks for the response, as I say I swapped the one next to it that was working. All 3 sensors didn't work in the position that isn't working but good in the other. ( Basically swapped between positions 2 & 3.
Thamks again
Dave

 

[Dave60]

Bumper looms on these and w213 are troublesome in my experience. Wires go green inside the insulation. New ones aren’t as expensive as you might expect

Hi
Thanks for the info, I hadn't thought of that. My next step was to look at changing out the Distronic Radar Sensor but looking at the price to replace the loom will probably be the cheaper option.
Do you know if they are individual for each model.
Regards
Dave

 

[OneForTheRoad]

Hi
Thanks for the info, I hadn't thought of that. My next step was to look at changing out the Distronic Radar Sensor but looking at the price to replace the loom will probably be the cheaper option.
Do you know if they are individual for each model.
Regards
Dave

Ring a dealer and ask but .Number:A2055404207 Will give you some idea . Good luck .

 

[Dave60]

An update for you all. OneForTheRoad the wiring loom you quoted was the right pt no for mine.
I changed it today but unfortunately the fault is still there. I cleared all the faults but the problem still exists. Fault code is B124E14. Can anyone help please as bar going to a main stealer I don't know what to change next.

 

[OneForTheRoad]

An update for you all. OneForTheRoad the wiring loom you quoted was the right pt no for mine.
I changed it today but unfortunately the fault is still there. I cleared all the faults but the problem still exists. Fault code is B124E14. Can anyone help please as bar going to a main stealer I don't know what to change next.

Have you Access to icarsoft scanner that shows all the sensors working or not working. ?

 

[Dave60]

No I haven't, I've used a Stethoscope and checked each individual sensor. All are clicking except the L/H Inner front. It's the 6 sensor system.

 

[OneForTheRoad]

No I haven't, I've used a Stethoscope and checked each individual sensor. All are clicking except the L/H Inner front. It's the 6 sensor system.

Buy a couple of Bosch sensors off eBay £10 each or so , have a look at your old sensors , if the sealant on the side looks worn, chances are it's letting in moisture.

Ideally you need a scanner or your simply guessing. It might even be the module that's failed??

 

[Dave60]

Do you think the working sensors could prevent the one that not working that I've replaced and swapped out with another on the bumper.

 

[OneForTheRoad]

Do you think the working sensors could prevent the one that not working that I've replaced and swapped out with another on the bumper.

It only takes one faulty sensor to put the 4 red lights on. Icarsoft scanner would tell you which one . if you have one new sensor ,you could swap it along the loom locations until it works properly. If not it's a few sensors or other issues.

 

[Dave60]

But all the other sensors are clicking when listened to them with the Stethoscope, bar the no 3 sensor. Even when I swapped the no 4 sensor which was working the 3 position didn't work. I would have thought that would mean it's a problem with that position rather than the sensor.

 

[OneForTheRoad]

But all the other sensors are clicking when listened to them with the Stethoscope, bar the no 3 sensor. Even when I swapped the no 4 sensor which was working the 3 position didn't work. I would have thought that would mean it's a problem with that position rather than the sensor.

In that case , new loom made no difference, swapping sensors made no difference, only leaves the module itself .

 

[Jobsworth]

There should be three wires to each sensor. One is a power feed, possibly 5v, one is an earth and one is the output signal that goes back to the control unit. The power and earth are the same for each sensor, ie they are connected to the same point. Only the signal wire is individual for each sensor. I would test for continuity back to the module first, but if continuity is good it’s module fault

 

[Dave60]

Firstly thanks for all the help. Do you mean the Distronic Radar Sensor behind the bumper that the wiring loom goes to or is there another parking sensor module on the car.

 

[Jobsworth]

The central radar sensor is not part of the parking sensor setup. It’s used for autonomous braking and intelligent cruise, if you have it

 

[OneForTheRoad]

Firstly thanks for all the help. Do you mean the Distronic Radar Sensor behind the bumper that the wiring loom goes to or is there another parking sensor module on the car.

Passenger footwell apparently.

Possibly

A0009001808​

 

[Dave60]

Passenger footwell apparently.

Possibly

A0009001808​

Thank you again for the info. Do you know which side of the passenger footwell it is.

 

[OneForTheRoad]

Thank you again for the info. Do you know which side of the passenger footwell it is.

No clue buddy , could even be under the seat . ??