Engine-Codes - Lexus - P0504 Lexus

P0504 Lexus Code - Brake Switch Circuit 'A' / 'B' Correlation

- Code Popularity: 24,411 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 1/3
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What are the Possible Causes of the DTC P0504 Lexus?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Stop Lamp Switch (Brake Switch)
  • Blown Stop Lamp Bulb
  • Stop Lamp Switch harness open or shorted
  • Stop Lamp Switch circuit poor electrical connection
  • Faulty Engine Control Module (ECM)
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How to Fix the DTC P0504 Lexus?

Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

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What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P0504 Lexus code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

What Does the P0504 Lexus Code Mean?

The Stop Lamp Switch is a duplex system that transmits two signals: STP and ST1-. These two signals are used by the Engine Control Module (ECM) to monitor whether or not the brake system is working properly. If the signals, which indicate the brake pedal is being depressed and released, are detected simultaneously, the ECM interprets this as a malfunction in the stoplight switch and sets the Diagnostic Trouble Code (DTC).

P0504 Lexus Code - Brake Switch Circuit 'A' / 'B' Correlation

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