B1471 – Lamp Headlamp Input Circuit Open

The ODBII code B1471 indicates that there is an open circuit in the headlamp input circuit, meaning the vehicle’s system is not detecting a proper signal from the headlamp switch or related components.

The severity of ODBII code B1471 Lamp Headlamp Input Circuit Open is moderate.

Common Causes For: B1470 Lamp Headlamp Input Circuit Failure

• Open circuit in the headlamp wiring
• Faulty headlamp switch
• Defective headlamp relay
• Bad ground connection
• Damaged or corroded connectors
• Faulty headlamp assembly
• Issues with the body control module (BCM)

Common misdiagnosis for B1471 Lamp Headlamp Input Circuit Open

• Faulty headlight bulb
• Bad headlight relay
• Damaged wiring or connectors
• Faulty body control module (BCM)
• Incorrectly installed headlight assembly
• Malfunctioning switch or control stalk
• Grounding issues
• Corroded terminals or connectors

Common Troubleshooting Steps

The OBD-II code B1471 indicates a problem with the headlamp input circuit, specifically that there is an open circuit. This can be caused by various issues, including wiring problems, faulty components, or issues with the vehicle’s body control module (BCM). Here are some common troubleshooting steps to diagnose and resolve the B1471 code:

• Visual Inspection: **Check Wiring and Connectors: Inspect the wiring harness and connectors related to the headlamp circuit for any signs of damage, corrosion, or loose connections.
• **Look for Shorts or Breaks: Look for any frayed wires or broken connections that could cause an open circuit.
• Check the Headlamp Bulbs: **Inspect Bulbs: Ensure that the headlamp bulbs are functioning properly. Replace any burnt-out bulbs.
• **Test Bulb Sockets: Check the bulb sockets for corrosion or damage.
• Test the Headlamp Switch: **Functionality Check: Ensure that the headlamp switch is functioning correctly. If the switch is faulty, it may not send the proper signal to the BCM.
• Check the Body Control Module (BCM): **Scan for Additional Codes: Use an OBD-II scanner to check for any other related trouble codes that may provide more context.
• **Inspect BCM Connections: Ensure that the BCM connectors are secure and free of corrosion.
• Perform Continuity Tests: **Test Wiring: Use a multimeter to perform continuity tests on the wiring between the headlamp and the BCM. Look for any breaks in the circuit.
• **Check Ground Connections: Ensure that the ground connections for the headlamp circuit are secure and functioning.
• Check Fuses: **Inspect Fuses: Check the fuses related to the headlamp circuit. Replace any blown fuses.
• Test the Relay (if applicable): **Check Relay Operation: If the vehicle uses a relay for the headlamp circuit, test the relay to ensure it is functioning properly.
• Clear Codes and Test Drive: **Clear the Code: After performing repairs, clear the trouble code using an OBD-II scanner.
• **Test Drive: Take the vehicle for a test drive to see if the code returns.
• Consult Repair Manual: **Refer to Vehicle-Specific Information: If the issue persists, consult the vehicle’s repair manual for specific diagnostic procedures related to the headlamp circuit.
• Seek Professional Help: **Contact a Mechanic: If you are unable to resolve the issue, it may be best to consult a professional mechanic for further diagnosis and repair. By following these steps, you should be able to identify and resolve the issue causing the B1471 code. Always ensure safety precautions are taken when working on electrical systems in vehicles.