B1872 – OBD-II DTC

OBD-II DTC B1872 – Turn Signal / Hazard Power Feed Circuit Short To Battery

DTC B1872 meaning

DTC B1872 refers to a diagnostic trouble code indicating a short circuit in the turn signal or hazard power feed circuit to the battery. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle systems for faults. When the power feed circuit experiences a short to battery, it can lead to improper functioning of the turn signals and hazard lights.

DTC B1872 symptoms

Common symptoms associated with DTC B1872 may include:

• Turn signals not functioning or blinking erratically
• Hazard lights not operating
• Dashboard warning lights illuminated
• Possible blown fuses related to the turn signal or hazard circuit

DTC B1872 causes

Several factors can lead to the occurrence of DTC B1872, including:

• Wiring issues such as frayed or damaged wires
• Corroded connectors in the turn signal or hazard circuit
• Faulty turn signal switch or hazard switch
• Short circuits caused by aftermarket modifications or installations
• Defective body control module (BCM) or other related control modules

DTC B1872 seriousness

DTC B1872 is considered a moderate to serious issue. While it may not immediately affect the vehicle’s drivability, it can compromise safety by impairing the visibility of turn signals and hazard lights. This can increase the risk of accidents, especially in low visibility conditions. It is advisable to address this code promptly to ensure proper vehicle operation and safety.

How to diagnose DTC B1872

To diagnose DTC B1872, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1872 code.
2. Inspect the vehicle’s wiring and connectors related to the turn signal and hazard circuits for any visible damage or corrosion.
3. Check the fuses associated with the turn signal and hazard lights for continuity.
4. Test the turn signal and hazard switches for proper operation.
5. Utilize a multimeter to check for voltage and ground at the turn signal and hazard circuits.
6. Examine the body control module (BCM) for any faults or issues.

How to fix DTC B1872 step-by-step instructions

To fix DTC B1872, follow these step-by-step instructions:

1. Clear the DTC using an OBD-II scanner.
2. Repair or replace any damaged wiring or connectors found during diagnosis.
3. Replace any blown fuses related to the turn signal or hazard circuit.
4. Replace faulty turn signal or hazard switches if necessary.
5. If the BCM is found to be defective, consider replacing it.
6. Recheck the system by performing a function test on the turn signals and hazard lights.
7. Use the OBD-II scanner to ensure the DTC does not return.

How to erase DTC B1872

To erase DTC B1872, 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. Access the diagnostic trouble codes menu on the scanner.
4. Select the option to clear or erase codes.
5. Confirm the action and wait for the scanner to complete the process.
6. Disconnect the scanner and start the vehicle to verify that the code does not reappear.

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