OBD-II DTC B1802 – Lamp Turn Signal Rear Output Circuit Failure
DTC B1802 meaning
DTC B1802 refers to a diagnostic trouble code indicating a failure in the rear turn signal output circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle functions and components. When the system detects an issue with the rear turn signal circuit, it triggers this specific code to alert the technician of the problem.
DTC B1802 symptoms
Common symptoms associated with DTC B1802 may include:
- Inoperative rear turn signals
- Flashing turn signal indicator on the dashboard
- Possible illumination of the check engine light
- Intermittent or erratic turn signal operation
DTC B1802 causes
Several factors can lead to the activation of DTC B1802, including:
- Faulty turn signal bulbs
- Damaged wiring or connectors in the turn signal circuit
- Defective turn signal relay or module
- Corrosion or poor connections at the rear light assembly
- Issues with the body control module (BCM) or other related control units
DTC B1802 seriousness
The seriousness of DTC B1802 can vary based on the specific symptoms and the vehicle’s overall condition. However, it is generally considered a moderate issue because:
- Inoperative turn signals can lead to unsafe driving conditions.
- It may result in legal penalties if the vehicle is not compliant with traffic laws.
- Ignoring the issue could lead to further electrical problems in the vehicle.
How to diagnose DTC B1802
To diagnose DTC B1802, follow these steps:
- Use an OBD-II scanner to confirm the presence of the B1802 code.
- Inspect the rear turn signal bulbs for any signs of damage or failure.
- Check the wiring and connectors for any visible damage or corrosion.
- Test the turn signal relay or module for proper operation.
- Examine the body control module (BCM) for any faults or issues.
How to fix DTC B1802 step-by-step instructions
To fix DTC B1802, follow these step-by-step instructions:
- Replace any faulty rear turn signal bulbs.
- Repair or replace damaged wiring or connectors in the turn signal circuit.
- Replace the turn signal relay or module if it is found to be defective.
- Clean any corrosion from connectors and ensure all connections are secure.
- Reprogram or replace the body control module (BCM) if necessary.
- Clear the DTC using an OBD-II scanner and test the turn signals to ensure proper operation.
How to erase DTC B1802
To erase DTC B1802, follow these steps:
- Connect an OBD-II scanner to the vehicle’s diagnostic port.
- Turn on the vehicle’s ignition without starting the engine.
- Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
- Confirm the action to clear the trouble codes.
- Disconnect the scanner and start the vehicle to verify that the code does not reappear.
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