B1305 – OBD-II DTC

OBD-II DTC B1305 – Accessory Delay Relay Coil Circuit Short To Ground

DTC B1305 meaning

DTC B1305 refers to a diagnostic trouble code indicating a problem with the accessory delay relay coil circuit. Specifically, it signifies that there is a short to ground in the relay coil circuit responsible for controlling the accessory delay feature in the vehicle. This feature allows certain electrical components to remain powered for a short period after the ignition is turned off.

DTC B1305 symptoms

Common symptoms associated with DTC B1305 may include:

• Accessory components not functioning properly.
• Delayed shutdown of electrical accessories after the ignition is turned off.
• Battery drain due to accessories remaining powered.
• Illumination of the check engine light or other warning lights on the dashboard.

DTC B1305 causes

Several factors can lead to the occurrence of DTC B1305, including:

• Faulty accessory delay relay.
• Wiring issues, such as damaged or frayed wires.
• Corrosion or poor connections in the relay circuit.
• Short circuits in the electrical system.
• Faulty body control module (BCM) or other related control modules.

DTC B1305 seriousness

The seriousness of DTC B1305 can vary based on the symptoms experienced. While it may not immediately affect vehicle drivability, it can lead to:

• Increased battery drain, potentially leading to a dead battery.
• Malfunctioning electrical accessories, which can be inconvenient.
• Potential damage to the electrical system if left unaddressed.

How to diagnose DTC B1305

To diagnose DTC B1305, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1305.
2. Inspect the accessory delay relay and its connections for any visible damage or corrosion.
3. Check the wiring harness for shorts, frays, or disconnections.
4. Test the accessory delay relay using a multimeter to ensure it operates correctly.
5. Examine the body control module for any faults or issues.
6. Clear the DTC and perform a road test to see if the code reappears.

How to fix DTC B1305 step-by-step instructions

To fix DTC B1305, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Locate the accessory delay relay and inspect it for damage or corrosion.
3. Replace the accessory delay relay if it is found to be faulty.
4. Inspect the wiring harness connected to the relay for any signs of wear or damage.
5. Repair or replace any damaged wiring or connectors as necessary.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Test the system by turning off the ignition and observing if the accessories turn off as expected.

How to erase DTC B1305

To erase DTC B1305, 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. Access the diagnostic trouble codes menu on the scanner.
4. Select the option to clear or erase the codes.
5. Confirm the action and wait for the scanner to indicate that the codes have been cleared.
6. Disconnect the scanner and perform a test drive to ensure the code does not reappear.

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