B2249 – OBD-II DTC

OBD-II DTC B2249 – Head Lamp Relay Coil Short to Battery

DTC B2249 meaning

DTC B2249 refers to a diagnostic trouble code indicating a short circuit in the headlamp relay coil to the battery. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. When the vehicle’s computer detects that the headlamp relay coil is receiving an unexpected voltage or is shorted to the battery, it triggers this code to alert the technician of a potential issue.

DTC B2249 symptoms

Common symptoms associated with DTC B2249 may include:

• Headlights not functioning or flickering
• Dashboard warning lights illuminated
• Inconsistent headlamp operation
• Increased battery drain
• Possible blown fuses related to the headlamp circuit

DTC B2249 causes

Several factors can lead to the occurrence of DTC B2249, including:

• Faulty headlamp relay
• Wiring issues, such as frayed or damaged wires
• Corrosion in electrical connectors
• Short circuits in the headlamp circuit
• Defective body control module (BCM)

DTC B2249 seriousness

The seriousness of DTC B2249 can vary. While it may not immediately affect the vehicle’s drivability, it can lead to safety concerns due to malfunctioning headlights. If left unaddressed, it may result in further electrical issues or damage to the vehicle’s electrical system. Therefore, it is advisable to diagnose and repair the issue promptly.

How to diagnose DTC B2249

To diagnose DTC B2249, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B2249 code.
2. Inspect the headlamp relay for any visible signs of damage or corrosion.
3. Check the wiring and connectors associated with the headlamp circuit for fraying or shorting.
4. Test the headlamp relay using a multimeter to ensure it operates correctly.
5. Examine the body control module for any faults or issues.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC B2249 step-by-step instructions

To fix DTC B2249, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and replace the headlamp relay if it is found to be faulty.
3. Repair or replace any damaged wiring or connectors in the headlamp circuit.
4. Clean any corrosion found on electrical connectors to ensure proper connectivity.
5. Test the body control module and replace it if necessary.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Perform a road test to confirm that the issue has been resolved and the code does not reappear.

How to erase DTC B2249

To erase DTC B2249, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the vehicle’s ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear Codes” option on the scanner.
4. Follow the prompts to clear the DTC from the vehicle’s computer.
5. Disconnect the scanner and turn off the ignition.
6. Start the vehicle and monitor for any reoccurrence of the code.

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