C0049 moderate

Left Rear Wheel Speed Sensor Erratic Signal

The C0049 code means the vehicle's onboard diagnostic system has detected: Left Rear Wheel Speed Sensor Erratic Signal. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$100 - $400 (parts and labor)
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Common Symptoms

  • ABS warning light on
  • Random traction control activation
  • Speedometer fluctuates
  • ABS engages during normal braking

Probable Causes (Ranked by Likelihood)

  • Damaged left rear tone ring Very High
  • Metallic debris on sensor tip High
  • Excessive wheel bearing play Moderate
  • Failing wheel speed sensor Low

Step-by-Step Diagnostic Procedure

  1. Clean left rear sensor tip of debris

  2. Check tone ring teeth for damage

  3. Inspect left rear wheel bearing for play

  4. Monitor sensor waveform with scan tool

Frequently Asked Questions

What does code C0049 mean?

C0049 indicates a problem with the left rear wheel speed sensor circuit causing erratic signal output.

Can I drive with code C0049?

You can drive short distances, but ABS and traction control will be disabled. Avoid slippery roads.

How much does it cost to fix C0049?

Wheel speed sensor repairs typically cost $100 to $400 including parts and labor.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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