C0050 on 2010-2017 Chevrolet Equinox: Causes and Fixes for the Right Rear Wheel Speed Sensor Circuit

What's Unique About the 2010-2017 Chevrolet EQUINOX

The 2010-2017 Equinox and its platform mates (GMC Terrain, Cadillac SRX) use a magnetic encoder ring integrated into the wheel bearing hub assembly. These rings are notoriously prone to collecting ferrous metallic road debris. As detailed in GM Technical Service Bulletin #PIC5428G, this debris disrupts the magnetic signal the sensor reads, triggering codes like C0050, 🎬 Watch: Diagnosing C0050 wheel speed sensor circuit codes. often with symptom bytes 18, 5A, or 0F. This makes cleaning the hub a crucial, platform-specific first diagnostic step that often resolves the issue without replacing any parts.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• ABS warning light is on
• StabiliTrak or Traction Control warning light is on
• "Service StabiliTrak" or "Service Traction Control" message in the driver information center
• "All-Wheel Drive Off" message on AWD models
• Heavier steering feel at low speeds, possibly with a "Service Power Steering" message and code U0415, as noted in TSB #PIC5428G.

Most Likely Causes

1. Debris on Wheel Bearing Magnetic Encoder Ring 🔴 High Probability The design of the wheel bearing seal allows ferrous metallic debris (rust flakes, brake dust) to accumulate on the magnetic ring the sensor reads. This is a well-documented issue covered by GM TSB #PIC5428G.
   How to confirm: Visually inspect the magnetic ring on the inboard side of the right rear wheel hub for rust flakes or a metallic 'fuzz'. This requires removing the wheel speed sensor (held by one bolt) and looking into the hole, often with a borescope or small camera.
   Typical fix: Gently clean the debris off the magnetic ring using a soft, non-magnetic brush (like a nylon bristle brush) and brake cleaner. Do not use magnets or harsh scrapers for cleaning as they can permanently damage the encoder ring. Reinstall the sensor, clear codes, and test drive.
   Est. part cost: $0-$15 for cleaning supplies
2. Failed Right Rear Wheel Speed Sensor 🟡 Medium Probability → Shop ABS Wheel Speed Sensor The sensor is exposed to harsh conditions (water, salt, heat) at the wheel, leading to eventual electronic failure or physical damage to its housing or wiring.
   How to confirm: Use a scan tool to monitor live data from all four wheel speed sensors while driving. If the right rear sensor's reading is erratic, drops to zero, or doesn't match the others, the sensor is likely bad. An oscilloscope can also be used to verify a noisy or missing square wave signal.
   Typical fix: Replace the right rear wheel speed sensor. It is typically held in by a single 10mm or Torx bolt.
   Est. part cost: $25-$75
3. Damaged or Cracked Wheel Bearing Magnetic Encoder Ring 🟡 Medium Probability Over time, the magnetic ring can become brittle from rust and exposure, causing it to crack, delaminate, or have chunks fall off. This creates a gap in the signal that the sensor cannot read correctly.
   How to confirm: After cleaning, visually inspect the brown magnetic ring on the hub for cracks, missing sections, or separation from the hub. If any physical damage is found, the entire hub must be replaced.
   Typical fix: Replace the entire right rear wheel hub and bearing assembly. This is a more involved repair requiring removal of the brake caliper, rotor, and axle nut.
   Est. part cost: $80-$200
4. Damaged Wiring or Connector ⚪ Low Probability The wiring harness is susceptible to damage. TSB PIT5427B specifically points to corrosion in the X411 connector, located under the rear of the vehicle behind and to the left of the fuel tank, as a cause for C0050 and many other codes. Rodent damage and internal wire breaks within the harness near this connector are also noted in TSB PIT5171C.
   How to confirm: Visually inspect the wiring harness from the sensor to the body. Unplug and inspect the sensor connector and the X411 connector for green or white corrosion, bent pins, or water intrusion. Perform a continuity test on the wires between the sensor connector and the EBCM.
   Typical fix: Repair the damaged section of wire or replace the pigtail connector. If the X411 connector is corroded, it may need to be de-pinned and cleaned or replaced.
   Est. part cost: $15-$40 for a pigtail connector

Rare But Worth Checking

• Failed Electronic Brake Control Module (EBCM): → Shop ABS Control Module This is very rare and should only be considered after all other possibilities (sensor, hub, and wiring) have been definitively ruled out. An EBCM failure typically triggers multiple, persistent codes, not just a single wheel speed sensor fault.

Diagnosis Steps

1. Connect an ABS-capable OBD-II scanner and confirm the presence of code C0050. Note any other codes, especially U-codes or codes for other wheels.
2. Use the scanner's live data function to monitor the speed of all four wheels while driving. Look for the Right Rear (RR) speed to be erratic, drop to zero, or not match the other wheels.
3. Lift and safely support the rear of the vehicle. Visually inspect the wheel speed sensor wiring and connector for any obvious damage, chafing, or corrosion.
4. Remove the single bolt (typically 10mm or T30) holding the right rear wheel speed sensor and carefully pull the sensor out of the hub.
5. Inspect the hole and the magnetic encoder ring on the hub assembly. Look for a buildup of metallic debris, which often looks like a dark paste or 'fuzz'.
6. If debris is present, use a soft nylon brush and brake cleaner to thoroughly clean the magnetic ring. Do not use magnetic tools. Reinstall the sensor, clear the codes, and test drive to see if the fault returns.
7. If no debris was found, or if cleaning did not fix the issue, carefully inspect the magnetic ring itself for cracks, missing sections, or delamination. If it's damaged, the entire hub assembly needs to be replaced.
8. If the ring is intact, the sensor is the next most likely culprit. Replace the right rear wheel speed sensor.
9. If the problem persists, locate and inspect the X411 connector under the rear of the vehicle (behind and left of the fuel tank) for corrosion, as per TSB PIT5427B.
10. If all else fails, perform continuity and resistance checks on the wiring harness between the sensor connector and the EBCM to rule out an internal wire break.

Parts You'll Likely Need

• Right Rear Wheel Hub and Bearing Assembly (OEM #13591999, 513288 (ACDelco Gold)) — This is the required fix if the magnetic encoder ring is found to be cracked or damaged. It is also a common failure point.
  Trusted brands: ACDelco, Moog, Timken, SKF
  OEM price range: $150-$250
  Aftermarket price range: $80-$150
• Right Rear ABS Wheel Speed Sensor (OEM #20938122) — If the magnetic ring is clean and intact, the sensor itself is the next most likely part to have failed electronically. This part number is shared for left and right rear.
  Trusted brands: ACDelco, Dorman, Standard Motor Products (SMP)
  OEM price range: $50-$90
  Aftermarket price range: $25-$50
• ABS Wheel Speed Sensor Connector Pigtail (OEM #PT2160 (ACDelco)) — Needed if the connector at the sensor is corroded, melted, or has broken wires.
  Trusted brands: ACDelco, Standard Motor Products, Dorman
  OEM price range: $25-$40
  Aftermarket price range: $15-$30

Related Codes That Often Appear With This One

• C0045 — This is the code for the Left Rear Wheel Speed Sensor. It's common to see issues on both rear wheels, especially related to debris or wiring problems in the X411 connector which serves both sides.
• U0415 — As noted in TSB #PIC5428G, a loss of a wheel speed sensor signal can cause the Power Steering Control Module to set this code ('Invalid Data Received From EBCM'), resulting in heavier steering at low speeds.
• C0035, C0040 — These are the codes for the front wheel speed sensors. If a systemic issue like a faulty EBCM or widespread wiring problem exists, codes for multiple wheels may appear.

Technical Service Bulletins (TSBs) & Recalls

• PIC5428G: Details the diagnostic procedure for wheel speed sensor codes (C0035-C0050) caused by debris on the magnetic encoder ring. It provides cleaning instructions and notes that this often fixes the problem without part replacement. It also mentions the link to code U0415 for the power steering.
• PIT5427B: Lists C0050 among many other codes that could be caused by a damaged or corroded X411 electrical connector located under the rear of the vehicle.
• PIT5171C: Discusses intermittent ABS/Stabilitrak messages and codes C0045/C0050 caused by internal wire breaks or rodent damage in the harness leading to the X411 connector.

Platform-Specific Known Issues

• As per TSB #PIC5428G, these vehicles are highly susceptible to metallic debris accumulating on the magnetic encoder ring of the wheel bearing, which can often be resolved by cleaning.

Mechanic-Grade Diagnostic Values

• Active Wheel Speed Sensor Power Supply — expected: Approximately 12V (Battery Voltage) at the sensor connector with key on, engine off.. Failure: No voltage indicates a wiring or EBCM supply issue.
• Wheel Speed Sensor Signal (Oscilloscope) — expected: A clean square wave that increases in frequency as the wheel is spun.. Failure: An erratic, noisy, or missing square wave indicates a faulty sensor or a problem with the magnetic encoder ring.
• Wheel Hub Assembly End Play — expected: Less than 0.005 inches.. Failure: End play exceeding 0.005 inches indicates a worn wheel bearing, which requires hub replacement. Excessive play can cause the encoder ring to move relative to the sensor, creating an erratic signal.

Hidden / Shadow Codes Worth Checking

• C0050 18: Low Signal Amplitude. This indicates the signal from the sensor is weak or erratic, often caused by debris on the magnetic encoder ring or a failing sensor. (see via A GM-specific scan tool like a Tech2 or GDS2, or a high-end professional scanner.)
• C0050 5A: Signal Not Plausible. The EBCM is receiving a signal, but it doesn't make sense compared to the other wheel speed sensors (e.g., reading 5 mph while others read 60 mph). This can be caused by a cracked encoder ring or an intermittent wiring issue. (see via A GM-specific scan tool like a Tech2 or GDS2, or a high-end professional scanner.)
• C0050 0F: Erratic Signal. The EBCM detects a very rapid and impossible change in wheel speed, such as a jump of 12 mph or more in 0.01 seconds. This points to a failing sensor or a significant crack in the encoder ring. (see via A GM-specific scan tool like a Tech2 or GDS2, or a high-end professional scanner.)
• C0050 00: General Circuit Malfunction. This indicates an open circuit, short to ground, or short to voltage in the sensor's wiring. (see via A GM-specific scan tool like a Tech2 or GDS2, or a high-end professional scanner.)

Wiring & Ground Locations

• X411 — Under the rear of the vehicle, located behind and to the left of the fuel tank.. This is a major inline connector for the rear body harness. As noted in TSB PIT5427B, corrosion inside this connector is a known cause for C0050 and C0045, as it carries the circuits for both rear wheel speed sensors.
• EBCM Connector — The Electronic Brake Control Module is located in the engine compartment, typically on the ABS hydraulic unit.. The Right Rear Wheel Speed Sensor wires terminate at the EBCM connector. On many GM trucks of this era, the wires are on pins 3 and 4. This is the final point to test continuity from if a wiring break is suspected.
• G401 / G403 — G401 is in the left side of the luggage compartment; G403 is in the right side.. These are the primary rear body ground points. While not directly on the sensor circuit (which is a floating two-wire circuit back to the EBCM), a poor ground at these locations can cause electrical interference and module communication issues that may manifest as various rear-of-vehicle faults.

Real Owner Repair Stories

• YouTube video from a professional technician (2017 GM Truck (Sierra)) — ABS and TCS lights on, active code C0050.
  ❌ Tried (didn't work) Visual inspection of the harness showed nothing obvious., The previous mechanic had already replaced the wheel speed sensor.
  ✅ What actually fixed it The technician found a corroded wire inside the harness right at the connector for the wheel speed sensor. After repairing the compromised wire and cleaning the connector, the code was resolved without replacing any major parts.

OEM Part Supersession History

• 15121067, 20763147 → 20938122 — Standard part evolution and consolidation.
  Heads up: Part 20938122 is the current correct OEM replacement for the rear wheel speed sensor on this platform and is interchangeable for left and right sides.
• 13500574, 13502873, 13577407, 13580091, 13598920 → 13591999 — Standard part evolution and consolidation for the rear hub assembly.
  Heads up: Part 13591999 is the current correct OEM replacement for the rear wheel hub and bearing assembly.