Blue sensor?

[CU58BEN]

Hello I hope someone can help me. I recently purchased my first MB, a GLA 180 Urban edition. Whilst going to my car today I noticed on the drivers side front wheel what looked like a blue sensor on a copper wire? I don’t know what it is and wasn’t sure it looked right? I have gone around the car and checked all the other wheels but one only appears visible on the drivers front wheel? No warning lights inside or anything just wasn’t sure if it should be displayed like that or if everything is fine and I’m just worrying? Any help would be much appreciated. Thank you

 

[markjay]

This looks to me like brake pad wear sensor.

That's what they look like:

It's normal to have the sensor only on one side. The assumption is that the pads on both sides will wear equally (unless there's a fault with the brakes on one side, obviously).

 

[CU58BEN]

Thanks Mark, I hope you are right. I couldn’t see one on any other wheel other than the drivers front so I was thinking maybe the others are hidden. I think I panicked because I saw copper. You can tell I haven’t got a clue thanks for you response!

 

[markjay]

The fact that the blue connector plug looks clean and shiny suggests that the front brake pads (and possibly also the discs) have been recently replaced - the wear sensor is replaced as a matter of course.

 

[Petrol Pete]

There is only one on each axle. 4 brake discs = 2 brake pad sensors. One on the front , one on the rear. Quite normal

 

[CU58BEN]

Thanks gents, it’s a 68 plate, one owner and I bought it from a used dealer (not main dealer) the car has only done 6,200 miles so they might be the original brakes hence why shiny etc. Good to know it looks ok though. Like I said I’ve gone round each wheel and the only visible connector and copper wires I see is the front driver wheel but sounds like I’m panicking about nothing.