Electronic Parking Brake Switch Circuit
The C0304 code means the vehicle's onboard diagnostic system has detected: Electronic Parking Brake Switch Circuit. This is a moderate severity code.
- 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
-
Scan for EPB-specific codes
-
Check EPB motor operation with scan tool
-
Inspect EPB wiring and connectors
-
Test EPB switch input signals
Frequently Asked Questions
What does code C0304 mean?
C0304 indicates a fault with the electronic parking brake switch circuit system in your vehicle.
Can I drive with C0304?
You can drive short distances but have the system inspected soon.
How much does it cost to fix C0304?
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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