Brake Switch Circuit ‘A’ / ‘B’ Correlation
Table of contents
P0504 TOYOTA Possible Causes
- Faulty stop lamp switch
- Blown stop lamp bulb
- Brake switch harness open or shorted
- Brake switch circuit poor electrical connection
How do I fix code P0504 TOYOTA?
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’s pins.
Cost of diagnosing the P0504 TOYOTA code
The cost of diagnosing the P0504 TOYOTA code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0504 TOYOTA Description
The stoplight 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).