B1794 – OBD-II DTC

OBD-II DTC B1794 – Lamp Headlamp Low-Beam Circuit Failure

DTC B1794 meaning

DTC B1794 refers to a diagnostic trouble code indicating a failure in the low-beam headlamp circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle systems for faults. When the vehicle’s computer detects an issue with the low-beam headlamp circuit, it triggers this specific code to alert the technician of the problem.

DTC B1794 symptoms

Common symptoms associated with DTC B1794 may include:

• Low-beam headlights not functioning
• Dashboard warning lights illuminated
• Inconsistent headlamp operation
• Possible flickering of the low-beam lights

DTC B1794 causes

Several factors can lead to the triggering of DTC B1794, including:

• Burnt out low-beam headlamp bulb
• Faulty headlamp relay
• Wiring issues, such as shorts or open circuits
• Defective headlamp switch
• Corrosion or poor connections in the headlamp circuit

DTC B1794 seriousness

The seriousness of DTC B1794 can vary. While it may not pose an immediate safety risk, non-functioning low-beam headlights can significantly impair visibility during nighttime driving or adverse weather conditions. It is advisable to address this issue promptly to ensure safe vehicle operation.

How to diagnose DTC B1794

To diagnose DTC B1794, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1794 code.
2. Inspect the low-beam headlamp bulbs for any signs of damage or burnout.
3. Check the headlamp relay for proper operation.
4. Examine the wiring and connectors for any signs of corrosion or damage.
5. Test the headlamp switch to ensure it is functioning correctly.
6. Perform continuity tests on the circuit to identify any breaks or shorts.

How to fix DTC B1794 step-by-step instructions

To fix DTC B1794, follow these step-by-step instructions:

1. Replace any burnt-out low-beam headlamp bulbs.
2. Replace a faulty headlamp relay if necessary.
3. Repair or replace damaged wiring or connectors in the headlamp circuit.
4. Replace the headlamp switch if it is found to be defective.
5. Clear the DTC using an OBD-II scanner after repairs are made.
6. Test the low-beam headlights to ensure they are functioning properly.

How to erase DTC B1794

To erase DTC B1794, 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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