B1302 – OBD-II DTC

OBD-II DTC B1302 – Accessory Delay Relay Coil Circuit Failure

DTC B1302 meaning

DTC B1302 refers to a fault in the Accessory Delay Relay Coil Circuit. This code indicates that the vehicle’s onboard diagnostic system has detected an issue with the relay responsible for controlling the accessory delay function, which keeps certain electrical components powered for a short time after the ignition is turned off.

DTC B1302 symptoms

Common symptoms associated with DTC B1302 may include:

• Accessory components not turning off after ignition is switched off
• Battery drain due to accessories remaining powered
• Malfunctioning interior lights or power windows
• Warning lights illuminated on the dashboard

DTC B1302 causes

Several factors can lead to the triggering of DTC B1302, including:

• Faulty accessory delay relay
• Wiring issues such as shorts or open circuits
• Corroded or loose electrical connections
• Faulty body control module (BCM)
• Software glitches in the vehicle’s computer system

DTC B1302 seriousness

DTC B1302 can be considered moderately serious. While it may not immediately affect the vehicle’s drivability, it can lead to battery drain and other electrical issues if not addressed. Ignoring this code may result in further electrical system complications over time.

How to diagnose DTC B1302

To diagnose DTC B1302, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the DTC.
2. Inspect the accessory delay relay for physical damage or corrosion.
3. Check the wiring and connectors associated with the relay for shorts or open circuits.
4. Test the relay operation using a multimeter to ensure it is functioning correctly.
5. Examine the body control module for any faults or software issues.

How to fix DTC B1302 step-by-step instructions

To fix DTC B1302, 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 diagnosis.
3. Clean any corroded connections to ensure proper electrical contact.
4. Reprogram or update the body control module if necessary.
5. Clear the DTC using an OBD-II scanner and test the system to ensure the issue is resolved.

How to erase DTC B1302

To erase DTC B1302, 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.
4. Select the option to clear or erase the trouble codes.
5. Disconnect the scanner and start the vehicle to verify that the code does not reappear.

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