The rear right wheel speed sensor detected a missing tooth on its tone ring, which is like a gear with notches that tells the ABS system how fast that wheel is spinning. If a tooth breaks off, the sensor can't read the wheel speed properly, confusing the anti-lock brake system.
The ECU monitors the frequency and consistency of tooth pulses from the rear right wheel speed sensor. When a tooth is missing from the tone ring, the pulse pattern becomes irregular, creating a gap in the expected signal. The ECU compares actual pulse intervals against expected thresholds and triggers a fault when deviation exceeds tolerance.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Tooth pulse interval variance | Consistent pulse spacing within ±5% tolerance | Pulse gap exceeding 10% or missing pulse cycle detected |
| Sensor signal amplitude | 0.5–5.0 mV peak-to-peak | Irregular or dropout signal during wheel rotation |