Front brake pads warning

[IWannaGoFast]

Hi guys need some advice, My warning light for front brake pad service is on, my pad thickness however is fine... I've taken it to bmw and they've done some checks and tell me the sensors are fine but each time I come home and the next day the light is back. It's super inconvenient to keep returning to bmw for the same thing...What can I tell them ?

FYI: when I take it back next week it will be for the 3rd time.

 

[Ralf*]

brake wear sensors work with two wires in and out, providing for a closed loop circuit (lights out)

when the brakes reach the wear limit, the sensor is rubbed thru to the point that the continuous loop is broken, thus triggering the light
any break in one of the two thin wires
!) chaffing against the rotating assembly (wheel/tyres/disk)
2) Incorrect or loose fitment of the quick release (Dzus fitting) inside the wheel arch
3) any other breakage point on the wire

I personally had the front wire chafe against the inside of my mag wheel, only visible once I took the wheel off, and this "broke" the circuit, setting off the light.

 

[cOlDFuSiOn]

+1 what Sir Ralf said. Also I have heard brake dust could also mess with the sensors.

 

[Ralf*]

another thing just came to mind

I am not familiar with the newer BMW's, but I have seen and heard comments made, that the OnBoard computor clock/time/date, is sometimes responsible for brake wear warnings, based purely on a "time", and even if the pads are OK, the computor gives warning that they need replacement.

this is my "rough" understanding, from what I have read/heard

maybe someone with a newer model and with better electrical/computor knowledge can weigh-in here.

 

[IWannaGoFast]

Thanks Ralf, I will speak to the bmw guys and have a look at the time settings as well:ty: