Pulse-gear fault

Possible cause(s) of fault:

• A pulse gear with an incorrect teeth number has been fitted
  
• One or more teeth have corroded
  
• Teeth have been joined by corrosion residues
  
• A wheel bearing is defective
  

Storage condition(s):

• If the detected speed of a wheel deviates considerably (at least 6 km/h). The fault is not set immediately, as the control unit attempts to compensate for speed deviations caused by different tyre pressures.
  

Troubleshooting procedure:

• Visual inspection as to whether one of the above error causes applies. On some models, this is not possible due to the design.
  
• Check of the signal level of the wheel speed sensor with the oscilloscope. If a wheel is turned with even speed, missing or defective teeth can be detected on the oscilloscope.
  

Note

• Manufacturing tolerances and tyre pressure differences cannot cause this fault