P0504 Lexus Code - Brake Switch Circuit 'A' / 'B' Correlation
Quick Answer
The P0504 diagnostic trouble code for Lexus vehicles specifically refers to the Brake Switch Circuit 'A' / 'B' Correlation. Common causes include Faulty brake switch, Damaged wiring or connectors in the brake switch circuit, Corrosion or poor connections in the brake switch circuit. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0504 Lexus indicates Brake Switch Circuit 'A' / 'B' Correlation.
- Common causes
- Common causes include Faulty brake switch, Damaged wiring or connectors in the brake switch circuit, Corrosion or poor connections in the brake switch circuit.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P0504 Lexus Description
The P0504 diagnostic trouble code for Lexus vehicles specifically refers to the Brake Switch Circuit 'A' / 'B' Correlation. This code indicates that there is a discrepancy between the signals being sent by the brake switch circuit 'A' and 'B'. The brake switch is a crucial component in the vehicle's braking system, as it sends signals to the engine control module (ECM) to indicate when the brake pedal is being pressed. This information is used by the ECM to adjust various systems such as the transmission, cruise control, and traction control.
Common Causes of P0504 Lexus
- Faulty brake switch
- Damaged wiring or connectors in the brake switch circuit
- Corrosion or poor connections in the brake switch circuit
- ECM software issue
Symptoms of P0504 Lexus
- Inoperative brake lights
- Transmission shifting erratically
- Cruise control not engaging or disengaging unexpectedly
- Traction control system malfunction
- Dashboard warning light illuminated
How to Fix P0504 Lexus
- Begin by diagnosing the issue with a professional OBD-II scanner to confirm the P0504 code.
- Inspect the brake switch for any visible damage or signs of wear.
- Check the wiring and connectors in the brake switch circuit for any corrosion or loose connections.
- Replace the brake switch if it is found to be faulty, and repair or replace any damaged wiring or connectors.
- Clear the trouble codes from the ECM and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P0504 Lexus
The typical repair costs for addressing the P0504 code in a Lexus vehicle can range from $100 to $300, depending on the specific components that need to be replaced and the labor involved. It's important to note that the diagnosis time and labor rates at auto repair shops can vary, so it's advisable to check with local shops for a more accurate estimate. Keep in mind that rates may be higher at dealerships or in metropolitan areas, while independent shops may offer lower prices.
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Frequently Asked Questions about P0504 Lexus Code
No Frequently Asked Questions about P0504 Lexus Code found.
Discuss the causes and fixes for P0504 Lexus OBDII Code
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What model and year is your Lexus? perhaps the stop lamp switch is obstructing the brake pedal.
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2003 Lexus LS430. I'm getting code P0504 with OBDII but with no SES or CE lights on dash. Brake light bulbs all seem to work normally with brake pedal press.
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i have the same code in my 2006 lexus is350, all brake lights work, replaced the brake pedal switch 3 times (2 times with an autozone one, and lastly an OEM one from japan that cost me $95 from the dealership) what the hell else could it be?
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How long it takes for brake switch to fail? within months, days, hours? if is within days or months, then the bracket where the switch is mounted may be bent or damage. If is within hours, then the problem is more than likely the wire from the sensor to the control unit.
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i can have the dealer clear the code, and within 30-45 minutes of highway driving, it will come back on. could it be a fuse? or do i just need to run new wire from the switch to the ECU?
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Check if you have battery voltage at terminals 2 and 3. There should be battery voltage with the ignition ON. If you have battery voltage and you know for your the switch is OK, then you can run a wire from the switch to ECM. Also, if you are planning to test wires with a test light, I recommend disconnecting the ECM first, you can easily damage the ECM with a test light.
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