B1303 – OBD-II DTC

OBD-II DTC B1303 – Accessory Delay Relay Coil Circuit Open

DTC B1303 meaning

DTC B1303 refers to an issue with the Accessory Delay Relay Coil Circuit, indicating that there is an open circuit in the relay coil. This means that the relay responsible for controlling accessory power is not functioning correctly, which can affect various electrical components in the vehicle.

DTC B1303 symptoms

Common symptoms associated with DTC B1303 may include:

• Accessory components not functioning properly
• Inability to turn on or off certain electrical features
• Battery drain due to accessories remaining powered
• Warning lights on the dashboard

DTC B1303 causes

The causes of DTC B1303 can include:

• Faulty accessory delay relay
• Wiring issues such as breaks or shorts in the circuit
• Corroded or loose connectors
• Faulty body control module (BCM)

DTC B1303 seriousness

DTC B1303 is considered a moderate issue. While it may not immediately affect the drivability of the vehicle, it can lead to electrical problems and potential battery drain if not addressed. It is advisable to diagnose and repair the issue promptly to avoid further complications.

How to diagnose DTC B1303

To diagnose DTC B1303, follow these steps:

1. Use an OBD-II scanner to confirm the DTC and check for any additional codes.
2. Inspect the accessory delay relay for any visible damage or corrosion.
3. Check the wiring and connectors associated with the relay for continuity and proper connections.
4. Test the relay operation by applying power directly to the coil and observing if it activates.
5. Examine the body control module for any faults or issues that may affect the relay operation.

How to fix DTC B1303 step-by-step instructions

To fix DTC B1303, follow these steps:

1. Replace the faulty accessory delay relay if it is determined to be defective.
2. Repair or replace any damaged wiring or connectors found during the diagnosis.
3. Ensure all connections are clean and secure to prevent future issues.
4. If the body control module is faulty, consider reprogramming or replacing it as necessary.
5. Clear the DTC using an OBD-II scanner and test the vehicle to ensure the issue is resolved.

How to erase DTC B1303

To erase DTC B1303, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the DTC menu on the scanner and select the option to clear or erase codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to check if the code returns.

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