C0371

Code

Generic C — Chassis

Right Rear Wheel Speed Sensor Circuit Fault

Brand: Generic

Type: C — Chassis

Views: UK: 9 EN: 14 RU: 15

AI status

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Page language: EN

Causes

Damaged or disconnected right rear wheel speed sensor
Broken, pinched, or corroded wiring or connector on the right rear sensor circuit
Short to battery voltage or short to ground in the sensor wiring
Contaminated or magnetized sensor, or excessive air gap to tone ring
Damaged or missing tone ring (ABS reluctor) or missing teeth
Wheel bearing or hub damage affecting sensor position

Symptoms

ABS warning lamp ON
Traction control/stability control warnings or disabled
Reduced or disabled ABS/traction control functions during braking or cornering
Diagnostic trouble code C0371 stored or active
Possible inconsistent speedometer reading (on some vehicles)
Occasional ABS activation or judder with normal braking if signal intermittent

What to check

Retrieve codes and freeze-frame data with a scan tool; check for related ABS/traction codes
Perform visual inspection of right rear sensor, connector, wiring loom, and tone ring for damage, corrosion or debris
Check for continuity and resistance of the sensor (compare to manufacturer spec or matching wheel)
Backprobe connector to verify reference voltage/supply and ground with ignition ON
Spin the wheel and observe signal with a DMM (AC for VR) or oscilloscope (recommended)
Wiggle harness and suspension while monitoring signal to reproduce intermittent faults

Signal parameters

Hall/active (most modern systems): 5 V reference, output 0–5 V square/pulse; frequency proportional to wheel speed
Variable reluctance (VR) sensor: AC sine output; amplitude ~0.1–3 V (increases with speed) and frequency proportional to wheel speed
Typical idle/low speed frequency: a few Hz; high speed can be hundreds of Hz depending on tone ring tooth count
Pulse count per wheel rotation depends on tone ring (common: 4–60 pulses per rev)
Expected DC resistance (if specified) typically 500–2000 ohm for active sensors; VR sensors may show low ohm values (check vehicle spec)

Diagnostic algorithm

Confirm code and related codes with scan tool; note freeze-frame and whether code is active or intermittent.
Perform visual inspection of right rear sensor, tone ring, connector, and wiring for obvious damage, contamination, or corrosion.
With ignition ON, backprobe connector: verify reference voltage (if present), and good ground. If no reference, trace to ABS module fuse/fuse link and wiring.
Measure sensor resistance (if applicable) and compare to spec. Check for short to ground or short to battery with an ohmmeter.
Spin wheel by hand (lift vehicle safely) and measure sensor output: AC volts for VR or digital pulses for Hall using oscilloscope or lab scope. Look for clean, consistent waveform and amplitude that changes with speed.
Wiggle harness, connectors, and suspension while monitoring signal to detect intermittent wiring faults.
Inspect tone ring for missing/broken teeth, heavy rust, or metal debris; verify proper air gap per spec.
If wiring and tone ring are good but signal missing or out of spec, swap with known-good sensor (if identical) or replace sensor and re-test.
After repair, clear codes and perform road test to confirm the fault does not return and ABS/traction systems operate normally.
If problem persists after sensor and wiring checks, consider ABS module/ECU inspection or repair at specialist service.

Likely causes

Connector corrosion or loose pin at the right rear sensor
Open or short in harness between sensor and ABS module (damage at suspension pivot points)
Failed right rear wheel speed sensor (internal short or open)
Contaminated sensor face or excessive air gap caused by bent mounting bracket or damaged tone ring
Damaged or missing tone ring teeth due to impact or corrosion

Fault status

⚠️ Status

Code may be stored as Active/present, Pending/intermittent, or History/faulted. Active codes indicate the fault is currently detected; pending means condition occurred but needs confirmation by the ECU.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5–1.5 hours