AutoCodes – Chevrolet – B0503 Chevrolet

B0503 Chevrolet Code - Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit

Quick Answer

The Body Control Module (BCM) provides control for the Right Daylight Running Lamp (DRL) relay circuit. Common causes include Faulty Right Daylight Running Lamp (DRL) Relay, Right Daylight Running Lamp (DRL) Relay harness is open or shorted, Right Daylight Running Lamp (DRL) Relay circuit poor electrical connection. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

What it means: B0503 Chevrolet indicates Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit.
Common causes: Common causes include Faulty Right Daylight Running Lamp (DRL) Relay, Right Daylight Running Lamp (DRL) Relay harness is open or shorted, Right Daylight Running Lamp (DRL) Relay circuit poor electrical connection.
Severity: Low - monitor the vehicle and repair when practical.
Can I drive?: The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

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Code Popularity 1,586

How popular is this code, among other codes? Low

Repair Importance Level

Low (Monitor) (1 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 11, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B0503 Chevrolet Description

The Body Control Module (BCM) provides control for the Right Daylight Running Lamp (DRL) relay circuit. The BCM grounds the RH DRL relay control circuit in order to energize the RH DRL relay and turn ON the RF turn signal. This allows the RF turn signal to be used for DRL and approach lighting functions. The BCM monitors the voltage level on the RH DRL relay control circuit. When the BCM commands the relay ON, the voltage level on the RH DRL relay control circuit should be low. When the relay is OFF, the voltage on the RH DRL relay control circuit should be high. If the BCM detects a voltage level other than expected, a malfunction is present and a Diagnostic Trouble Code (DTC) will set.

OBDII Code B0503 Chevrolet - Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit - AutoCodes.com — B0503 Chevrolet Code - Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit

What does this mean?

What are the Possible Causes of the DTC B0503 Chevrolet?

Faulty Right Daylight Running Lamp (DRL) Relay
Right Daylight Running Lamp (DRL) Relay harness is open or shorted
Right Daylight Running Lamp (DRL) Relay circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B0503 Chevrolet?

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 B0503 Chevrolet 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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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B0503 Chevrolet Code

1. What are the common symptoms of OBDII code B0503 in a Chevrolet related to the RH DRL relay control circuit?

The common symptoms include inoperative right-hand daytime running lights (DRLs), dim or flickering DRLs, or a warning light on the dashboard indicating a lighting system issue.

2. What does the OBDII code B0503 indicating a short to voltage or BCM open internally in the RH DRL relay control circuit mean?

This code suggests a potential electrical fault in the right-hand daytime running light relay control circuit, which could be caused by a short to voltage or an internal open circuit within the Body Control Module (BCM).

3. What are the possible causes of OBDII code B0503 in a Chevrolet pertaining to the RH DRL relay control circuit?

Possible causes include damaged wiring or connectors in the DRL circuit, a faulty DRL relay, a malfunctioning BCM, or a short to voltage in the circuit.

4. How can I diagnose and repair OBDII code B0503 in a Chevrolet with a suspected short to voltage in the RH DRL relay control circuit?

To diagnose this issue, conduct a thorough visual inspection of the DRL circuit wiring, check the DRL relay for proper operation, and use a multimeter to test for shorts to voltage. Repair involves addressing any damaged wiring, replacing the faulty components, or repairing the BCM if necessary.

5. Is it safe to continue driving my Chevrolet if OBDII code B0503 related to the RH DRL relay control circuit is present?

It is not recommended to drive the vehicle with unresolved lighting system issues, as it can compromise your safety and the safety of others on the road. Address the problem promptly to ensure proper functioning of the DRL system.

6. Can a DIY enthusiast with basic automotive knowledge fix OBDII code B0503 in a Chevrolet related to the RH DRL relay control circuit?

While some basic troubleshooting like checking fuses and visually inspecting wiring can be done by DIY enthusiasts, diagnosing and repairing electrical faults like those related to the DRL relay control circuit might require more advanced knowledge and tools. It's advisable to seek professional help if needed.

7. How much can I expect to pay for repairing OBDII code B0503 in a Chevrolet concerning the RH DRL relay control circuit?

The cost of repair can vary depending on the exact cause of the issue, the labor rates in your area, and whether any components need replacement. It's recommended to obtain quotes from reputable automotive repair shops for an accurate estimate.

8. Will resetting the OBDII code B0503 in a Chevrolet related to the RH DRL relay control circuit make the problem go away?

Resetting the code without addressing the underlying issue will not solve the problem permanently. It's crucial to diagnose the root cause of the code and perform the necessary repairs to ensure the proper functioning of the DRL system.

9. Are there any preventive maintenance measures I can take to avoid encountering OBDII code B0503 in a Chevrolet regarding the RH DRL relay control circuit in the future?

Regularly inspecting the lighting system, including the DRL circuit, for any signs of wear or damage, and addressing any issues promptly can help prevent the occurrence of this code. Keeping the electrical system well-maintained can also contribute to avoiding such faults.

10. Can extreme weather conditions or environmental factors contribute to triggering OBDII code B0503 in a Chevrolet related to the RH DRL relay control circuit?

Extreme weather conditions or exposure to moisture can potentially exacerbate electrical issues in the DRL relay control circuit, leading to faults like short to voltage or BCM internal open circuits. Protecting the vehicle from harsh environmental conditions can help prevent such problems.