B1873 – OBD-II DTC

OBD-II DTC B1873 – Turn Signal / Hazard Power Feed Circuit Short To Ground

DTC B1873 meaning

DTC B1873 refers to a diagnostic trouble code indicating a short circuit to ground in the turn signal or hazard power feed 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 control module detects an abnormal voltage level in the turn signal or hazard circuit, it triggers this code to alert the technician of a potential issue.

DTC B1873 symptoms

Common symptoms associated with DTC B1873 may include:

• Inoperative turn signals
• Inoperative hazard lights
• Dashboard warning lights illuminated
• Flashing or erratic turn signal operation
• Possible blown fuses related to the turn signal or hazard circuit

DTC B1873 causes

Several factors can lead to the triggering of DTC B1873, including:

• Damaged wiring or connectors in the turn signal or hazard circuit
• Moisture intrusion causing corrosion
• Faulty turn signal switch
• Short circuit due to improper installation of aftermarket accessories
• Defective body control module (BCM)

DTC B1873 seriousness

DTC B1873 is considered a moderate to serious issue. While it may not immediately affect the vehicle’s drivability, it can compromise safety by rendering turn signals and hazard lights inoperative. This can increase the risk of accidents, especially in low visibility conditions or during lane changes. It is advisable to address this code promptly to ensure safe vehicle operation.

How to diagnose DTC B1873

To diagnose DTC B1873, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1873 code.
2. Inspect the vehicle’s wiring and connectors related to the turn signal and hazard circuits for visible damage or corrosion.
3. Check the fuses associated with the turn signal and hazard lights for continuity.
4. Test the turn signal switch for proper operation using a multimeter.
5. Examine the body control module (BCM) for any faults or issues.
6. Perform a continuity test on the power feed circuit to check for shorts to ground.

How to fix DTC B1873 step-by-step instructions

To fix DTC B1873, follow these steps:

1. Repair or replace any damaged wiring or connectors found during the diagnosis.
2. Replace any blown fuses related to the turn signal or hazard circuit.
3. If the turn signal switch is faulty, replace it with a new one.
4. Address any issues found with the body control module (BCM), which may involve reprogramming or replacement.
5. Ensure all connections are secure and free from corrosion.
6. Clear the DTC using an OBD-II scanner and test the system to ensure proper operation.

How to erase DTC B1873

To erase DTC B1873, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position 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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