P0504 Scion Code - Brake Switch Circuit 'A' / 'B' Correlation
Quick Answer
The Stop Lamp Switch is a duplex system that transmits two signals: STP and ST1-. Common causes include Faulty Stop Lamp Switch (Brake Switch), Blown Stop Lamp Bulb, Stop Lamp Switch harness open or shorted. 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 Scion indicates Brake Switch Circuit 'A' / 'B' Correlation.
- Common causes
- Common causes include Faulty Stop Lamp Switch (Brake Switch), Blown Stop Lamp Bulb, Stop Lamp Switch harness open or shorted.
- 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.
Code P0504 Scion Description
What are the Possible Causes of the DTC P0504 Scion?
- 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)
How to Fix the DTC P0504 Scion?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0504 Scion code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0504 Scion Code
No Frequently Asked Questions about P0504 Scion Code found.
Discuss the causes and fixes for P0504 Scion OBDII Code
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I noticed for the past several months that when I stepped on the brakes with the A/C turned on it would loose power or my mph gage would drop lower than normal (idle). Could my Brake Light Switch some how be the cause of this issue? I had a friend use his machine to diagnose any issues and the only thing that he could get off of his machine was the P0504 code for my Brake Light Switch Circuit 'A'/'B' Correlation.
When the car is on and the A/C is not running everything operates perfectly fine no issues or problems with anything. As soon as I turn on the A/C is when everything from constant vibrations and a lower idle start to take place. Does any one out there own a scion XD and have had similar problems with the vehicle? I would greatly appreciate some help or feedback about this issue I'm having.
I did not take it in to the dealer ship yet. I was hoping to get some answers first to better understand the problem.
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