Chassis, generic

C051B Right Rear Wheel Speed Sensor - Mechanical

Check engine lightUsually off

EmissionsNot relevant

Drive cycleRequired

Limp modePossible

C051B covers a mechanical defect at the right rear wheel. No public manufacturer document defines when it is set; the cases known from bulletins carry other codes. They still show what to inspect at a right rear wheel. GM's 2018 program 18316 for Express and Savana vans found that axle vibration over rumble strips shook the right rear sensor signal into erratic values, and changed the brake module calibration rather than any part. Ford's message on the F-53 chassis covers tone rings deformed while hub and rotor were refitted. Infiniti's sensor bulletin adds loose or corroded tone wheels and bearings to the list. A mechanical code therefore calls for a look at encoder, bearing and sensor fit before electrical testing.

Likely causes

Right rear tone ring deformed or corroded

Right rear hub bearing loose or worn

Axle vibration disturbing the signal on rough surfaces

Symptoms

ABS, stability and traction lamps after rough stretches
Driver aids unavailable until the next ignition cycle

Repair estimate

DifficultyMediumDIY possible

Parts and labour€0–600

Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

wss rrtone ring rr

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.