23954 Front Wheel Speed Sensor

[sonia]

Hello,
    I am getting a solid Brake Failure light on my bike. On checking with 911, error code shows  - "23954 Front Wheel Speed Sensor". This only started occuring after I had my tires changed. Initial the Brak Failure would go away and return at about 30mph. I losed up the front sensor and cleaned it and now the brake failure light turns on at higher speeds around 80mph and after about 10-15 mins of riding. Any thoughts on how I can resolve?
 
error -  "23954 Front Wheel Speed Sensor : Signal implausible The fault is not present now"

BMW R1200RT 2010

[Alexm1]

Sonia, not sure what bike you have but likely it is the adjustment of the sensor to the sensor ring, particularly as it changed when you cleaned the sensor. Also check the sensor ring for damage since you have just changed the tyre.

[sonia]

Alex, bike is 1200rt 2010
Sensor Ring? Is that the metal ring with slots? or are you refering to something else.

[Alexm1]

Sonia, it is the metal ring with slots. The sensor reads the "gaps" (slots) and the clearance is adjustable. On mine it is .2 to 1.5mm. With the front wheel off the ground spin the wheel and check that the gap is constant, ie. that the sensor ring is not bent or damaged. Then adjust it for the correct clearance.

[Jughead]

My guess here would be that they did not clip the sensor cable back into its clip after removing the calliper to get the wheel out.  The disk has now chewed through the cable.  Follow the cable down the LHS fork leg.  Where it is in line with the outer edge f the disk you will find the damaged portion of the cable.

[sonia]

yes I did check the gap and its a little less then 2mm. The spacing between ring and sensor is consistant. I will have to take another 30mins ride to see if it will show up again. Will advise.
On another note, how does one adjust the spacing? Is that done from the ring or the sensor?

[Jughead]

It is done from the sensor using shims between the sensor and fork leg.

[sonia]

Just wanted to update this thread and bring it to a close.
I was able to resolve the issue.
I cleaned the sensor and the slots(although it looked fine) and I also reseated the sensor. Went for a half-day ride and all is well.
Thank for all the help and directions.

[Jughead]

[emoji106]