C0037
Left Rear Wheel Speed Sensor Signal Erratic
Moderatesensor
Overview
The C0037 diagnostic trouble code means the chassis control module has identified a left rear wheel speed sensor signal erratic problem. This code indicates that a chassis sensor or its circuit is not providing expected readings to the ABS/stability control system. Accurate sensor data is essential for the proper operation of anti-lock brakes, traction control, and electronic stability control, and a fault in this circuit can cause these safety systems to be disabled.
Symptoms
- Traction control warning light on
- Cruise control will not engage
- Steering angle or center position incorrect
- Ride height abnormal or uneven
Common Causes
- Faulty steering angle sensor
- Failed yaw rate or lateral accelerometer sensor
- Corroded or broken sensor wiring/connector
- Damaged wheel bearing causing sensor misalignment
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored chassis trouble codes and freeze frame data
- 2Monitor wheel speed sensor signals using scan tool live data while driving
- 3Inspect the affected sensor and its wiring connector for damage or corrosion
- 4Check the sensor air gap and tone ring for damage, debris, or excessive wear
- 5Test the sensor resistance and voltage output with a multimeter; compare to specifications
Estimated Repair Cost
$100 — $500
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Honda CivicFord FocusToyota CorollaKia Optima
Related Codes
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LowFrequently Asked Questions
The most common causes are a faulty sensor, damaged tone ring, excessive air gap, metallic debris on the sensor tip, corroded wiring, or a worn wheel bearing that allows the sensor to lose alignment with the tone ring.