C0309 moderate

Electronic Parking Brake Position Sensor

The C0309 code means the vehicle's onboard diagnostic system has detected: Electronic Parking Brake Position Sensor. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$300 - $800 (parts and labor)
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Common Symptoms

  • Parking brake warning light on
  • Electronic parking brake will not engage
  • Electronic parking brake will not release
  • Parking brake indicator flashing

Probable Causes (Ranked by Likelihood)

  • Failed EPB motor or actuator Very High
  • Damaged EPB wiring harness High
  • Corroded EPB connector Moderate
  • EPB control module failure Low

Step-by-Step Diagnostic Procedure

  1. Scan for EPB-specific codes

  2. Check EPB motor operation with scan tool

  3. Inspect EPB wiring and connectors

  4. Test EPB switch input signals

Frequently Asked Questions

What does code C0309 mean?

C0309 indicates a fault with the electronic parking brake position sensor system in your vehicle.

Can I drive with C0309?

You can drive short distances but have the system inspected soon.

How much does it cost to fix C0309?

Typical repair costs are $300 - $800 (parts and labor).

Sources

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

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