B1470 – Lamp Headlamp Input Circuit Failure

The ODBII code B1470 indicates a failure in the input circuit for the headlamp, which may involve issues with the wiring, connectors, or the headlamp control module.

The severity of ODBII code B1470 Lamp Headlamp Input Circuit Failure is generally considered moderate.

Common Causes For: B1469 Chime Input Request Circuit Open

• Faulty headlamp assembly
• Damaged wiring or connectors
• Short circuit in the headlamp circuit
• Corroded connectors
• Failed headlamp relay
• Malfunctioning body control module (BCM)
• Incorrectly installed or incompatible headlamp bulbs
• Grounding issues in the headlamp circuit

Common misdiagnosis for B1470 Lamp Headlamp Input Circuit Failure

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

Common Troubleshooting Steps

The OBD-II code B1470 indicates a “Lamp Headlamp Input Circuit Failure.” This code typically relates to issues with the headlamp system, specifically the input circuit that communicates the status of the headlamps to the vehicle’s control module. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check for Additional Codes: Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are multiple issues.
• Inspect Headlamp Bulbs: Check the headlamp bulbs to ensure they are functioning properly. Replace any burnt-out bulbs.
• Examine Wiring and Connectors: Inspect the wiring and connectors associated with the headlamp circuit for any signs of damage, corrosion, or loose connections. Pay special attention to the connectors at the headlamp assembly and the control module.
• Test the Headlamp Switch: Verify that the headlamp switch is functioning correctly. A faulty switch can prevent the headlamps from receiving power.
• Check Fuses: Inspect the fuses related to the headlamp circuit. Replace any blown fuses and check for any underlying issues that may have caused the fuse to blow.
• Test the Headlamp Relay: If your vehicle uses a relay for the headlamp circuit, test the relay to ensure it is functioning properly. Swap it with a similar relay (if available) to see if the issue persists.
• Measure Voltage and Ground: Use a multimeter to check for proper voltage at the headlamp connector. Ensure that there is a good ground connection as well.
• Inspect the Control Module: If all other components check out, the issue may lie within the vehicle’s control module. Check for any software updates or recalls related to the control module.
• Perform a Visual Inspection: Look for any signs of water intrusion or physical damage in the headlamp assembly and surrounding areas.
• Clear Codes and Test Drive: After performing the necessary repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns.1
• Consult a Professional: If the issue persists after following these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the B1470 code.