B1807 – OBD-II DTC

OBD-II DTC B1807 – Lamp Tail Output Circuit Open

DTC B1807 meaning

DTC B1807 refers to a diagnostic trouble code indicating an open circuit in the tail lamp output circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. The tail lamp output circuit is responsible for controlling the operation of the vehicle’s tail lights, which are crucial for visibility and safety during nighttime driving or in low-light conditions.

DTC B1807 symptoms

When DTC B1807 is triggered, the following symptoms may be observed:

• Tail lights not functioning or flickering
• Dashboard warning lights illuminated
• Inconsistent operation of other lighting systems
• Possible issues with related electrical components

DTC B1807 causes

Several factors can lead to the occurrence of DTC B1807, including:

• Open or damaged wiring in the tail lamp circuit
• Faulty tail lamp assembly or connectors
• Defective body control module (BCM)
• Corrosion or poor connections in the electrical system

DTC B1807 seriousness

DTC B1807 is considered a moderate to serious issue. While it may not immediately affect the drivability of the vehicle, it poses a significant safety risk due to non-functioning tail lights. This can lead to reduced visibility for other drivers, increasing the likelihood of accidents. It is essential to address this code promptly to ensure safe operation of the vehicle.

How to diagnose DTC B1807

To diagnose DTC B1807, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1807 code.
2. Inspect the tail lamp assembly for any visible damage or corrosion.
3. Check the wiring and connectors for signs of wear, fraying, or disconnection.
4. Test the tail lamp circuit with a multimeter to check for continuity.
5. Examine the body control module for any faults or error codes.

How to fix DTC B1807 step-by-step instructions

To fix DTC B1807, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors in the tail lamp circuit.
3. Replace any faulty tail lamp assemblies or bulbs as needed.
4. Clean any corrosion from connectors and ensure all connections are secure.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the tail lights to ensure they are functioning correctly.

How to erase DTC B1807

To erase DTC B1807, 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 DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes from the vehicle’s memory.
5. Disconnect the scanner and start the vehicle to verify that the code does not reappear.

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