B1347 – OBD-II DTC

OBD-II DTC B1347 – Heated Backlite Relay Circuit Failure

DTC B1347 meaning

DTC B1347 refers to a fault in the Heated Backlite Relay Circuit. This code indicates that the vehicle’s onboard diagnostic system has detected a malfunction in the relay responsible for controlling the heated backlite, which is typically part of the rear window defrosting system. The heated backlite is essential for improving visibility during cold weather conditions by clearing frost or ice from the rear window.

DTC B1347 symptoms

Common symptoms associated with DTC B1347 may include:

• Heated backlite not functioning
• Warning lights illuminated on the dashboard
• Inconsistent operation of the rear defrost system
• Possible issues with other electrical components in the vehicle

DTC B1347 causes

Several factors can lead to the triggering of DTC B1347, including:

• Faulty heated backlite relay
• Wiring issues, such as shorts or open circuits
• Corrosion or poor connections in the relay circuit
• Defective control module or software issues

DTC B1347 seriousness

The seriousness of DTC B1347 can vary. While it may not pose an immediate safety risk, it can affect visibility during adverse weather conditions, which can lead to dangerous driving situations. Additionally, if left unaddressed, it may indicate underlying electrical issues that could affect other systems in the vehicle.

How to diagnose DTC B1347

To diagnose DTC B1347, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the heated backlite relay for any visible damage or corrosion.
• Check the wiring and connectors associated with the relay for shorts or open circuits.
• Test the relay operation using a multimeter to ensure it is functioning correctly.
• Examine the vehicle’s control module for any software updates or faults.

How to fix DTC B1347 step-by-step instructions

To fix DTC B1347, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety.
2. Locate the heated backlite relay and inspect it for damage.
3. If the relay is faulty, replace it with a new one.
4. Check and repair any damaged wiring or connectors in the relay circuit.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the heated backlite to ensure it is functioning properly.

How to erase DTC B1347

To erase DTC B1347, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the ignition without starting the engine.
• Navigate to the DTC menu on the scanner.
• Select the option to clear or erase the codes.
• Confirm the action and wait for the scanner to complete the process.
• Disconnect the scanner and start the vehicle to ensure the code does not return.

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