B1799 – OBD-II DTC

OBD-II DTC B1799 – Lamp Turn Signal Front Output Circuit Open

DTC B1799 meaning

DTC B1799 refers to a diagnostic trouble code indicating an issue with the lamp turn signal front output circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the front turn signal lamp circuit, which can prevent the turn signal from functioning properly.

DTC B1799 symptoms

Common symptoms associated with DTC B1799 may include:

• Inoperative front turn signal lights
• Illuminated warning lights on the dashboard
• Flashing turn signal indicator at an abnormal rate
• Possible malfunction of other related lighting systems

DTC B1799 causes

The causes of DTC B1799 can vary, but typical reasons include:

• Open circuit in the front turn signal wiring
• Faulty turn signal bulb
• Defective turn signal relay
• Corroded or loose electrical connections
• Issues with the body control module (BCM)

DTC B1799 seriousness

DTC B1799 is considered a moderate issue. While it may not immediately affect the vehicle’s drivability, it can compromise safety by impairing the driver’s ability to signal turns or lane changes. It is advisable to address this code promptly to ensure proper vehicle operation and safety on the road.

How to diagnose DTC B1799

To diagnose DTC B1799, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1799 code.
2. Inspect the front turn signal bulbs for any signs of damage or failure.
3. Check the wiring and connectors for any visible damage, corrosion, or loose connections.
4. Test the turn signal relay for proper operation.
5. Utilize a multimeter to check for continuity in the turn signal circuit.
6. Examine the body control module for any faults or issues.

How to fix DTC B1799 step-by-step instructions

To fix DTC B1799, follow these step-by-step instructions:

1. Replace any faulty front turn signal bulbs.
2. Repair or replace damaged wiring or connectors in the turn signal circuit.
3. Replace the turn signal relay if it is found to be defective.
4. Ensure all electrical connections are clean and secure.
5. If necessary, reprogram or replace the body control module.
6. Clear the DTC using an OBD-II scanner and test the turn signals to ensure proper operation.

How to erase DTC B1799

To erase DTC B1799, 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.
5. Disconnect the scanner and start the vehicle to verify that the code does not reappear.

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