What it means
C0050 indicates the ABS/ESC module has detected a fault in the right-rear (RR) wheel speed sensor circuit. Like C0045, it’s typically triggered by an open/short in the RR circuit, sensor failure, or an erratic/missing signal; related references group it with the other wheel-speed circuit DTCs (C0035/C0040/C0045). RepairPal.com
Symptoms
- ABS lamp on; traction/stability control may be disabled.
- Vehicle messages such as “Service Brake Assist / StabiliTrak / Brake System” can appear on some GM platforms. SSForums
Severity / priority
High (safety-related). ABS/ESC performance is reduced or unavailable until the fault is corrected. RepairPal.com
Common causes
- Failed RR wheel speed sensor.
- Wiring/connector issues at the knuckle or along the rear harness (open, short-to-ground/battery, corrosion).
- Encoder/tone ring damage or incorrect air gap.
- Less common: ABS/EBCM input circuit fault. RepairPal.com
Diagnostic notes
- Check live data: compare RR speed to the other wheels while driving straight at a steady speed; RR that drops out/flat-lines suggests sensor/circuit. RepairPal.com
- Perform visual and circuit testing at the sensor and first connector; verify supply/ground for active sensors and waveform quality for passive sensors.
- Inspect the hub encoder for cracks/rust or missing segments; replace the hub if compromised.
- Intermittent RR codes often trace to harness damage near the wheel well or a failing pigtail; scope testing helps pinpoint intermittent dropouts. Mitchell 1®
Possible fixes
- Clean/reseat or replace the RR wheel speed sensor.
- Repair/replace damaged wiring/connector sections; ensure proper strain relief and sealing.
- Replace the hub/bearing if encoder damage is found.
- If the circuit and sensor are good but the DTC persists, follow service-manual tests for the ABS/EBCM channel. RepairPal.com
Sources: RepairPal overview linking C0050 to RR wheel speed sensor circuit (and grouping related wheel-speed codes); Mitchell1 SureTrack case study diagnosing C0050 on a Chevrolet Tahoe (harness/sensor/module findings); platform examples of driver-information warnings tied to C0050. RepairPal.com+2Mitchell 1®+2