C0031ABS / Traction

Left Front Wheel Speed Sensor Circuit (GM)

C0031 indicates a fault in the left front wheel speed sensor circuit on many GM vehicles. The ABS module cannot read that wheel, so it disables ABS, traction, and stability control.

🚗 Yes, but ABS and traction control are likely disabled, so fix it soon.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Failed wheel speed sensor$60-$250

45%

The left front wheel speed sensor has failed or corroded.

#2Wiring or connector damage$50-$300

30%

Harness damage or corrosion near the front wheel.

#3Damaged tone/reluctor ring$100-$400

15%

Damage to the ring the sensor reads.

#4Excessive air gap or debris$0-$100

10%

Debris or a loose sensor corrupts the signal.

🩺 Common Symptoms

ABS warning light on
Traction and stability control lights on
ABS may not activate in a hard stop
Wheel speed drops out in live data

💰 Repair Cost: DIY vs Shop

DIY Cost

$60-$300

Shop Cost

$150-$450

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose C0031

1Scan and confirm the left front sensor

2Inspect the sensor, connector, and tone ring

3Check wiring continuity and the sensor air gap

4Compare live wheel speed data across all wheels

❓ Frequently Asked Questions

Can I drive with C0031?

Yes, normal braking works, but ABS and traction control may be off. Drive carefully and fix it soon.

How much to fix C0031?

A wheel speed sensor is typically $150-$450 installed, or less if you DIY.

What causes C0031 most often?

A failed left front wheel speed sensor or damaged wiring at that wheel.

🔗 Related Codes

C0035C0037C0040C0045