P0504

Brake Switch A/B Correlation

Severity: Medium Brake System Generic OBD-II Code Est. Repair: $40 - $150

Schedule diagnosis soon. Continued driving may worsen the issue.

What Does P0504 Mean?

Two brake switch signals do not agree. Can affect cruise and TCC.

Common Symptoms

CEL
Cruise may not engage
Possible shift issues

Possible Causes

Misadjusted or failed brake light switch
Wiring
Burned brake bulbs affecting circuit

How to Fix P0504 – Repair Guide

Verify brake lights
Adjust or replace switch
Inspect bulbs and wiring
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Recommended OBD2 Scanners & Tools

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Disclaimer: Information is for educational reference only and does not replace professional diagnosis. Actual causes and costs vary by vehicle make, model, year and condition. Always verify with a qualified technician.