B1795 – Lamp Headlamp Low-Beam Circuit Open

The ODBII code B1795 indicates that there is an open circuit in the low-beam headlamp circuit, meaning the system is not detecting the low-beam headlamp as functioning properly.

The severity of ODBII code B1795 is moderate.

Common Causes For: B1794 Lamp Headlamp Low-Beam Circuit Failure

• Open circuit in the low-beam headlamp wiring
• Faulty low-beam headlamp bulb
• Defective headlamp relay
• Poor ground connection
• Damaged or corroded connectors
• Faulty body control module (BCM)
• Blown fuse in the headlamp circuit

Common misdiagnosis for B1795 Lamp Headlamp Low-Beam 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
• Faulty fuse or fuse box issues

Common Troubleshooting Steps

The OBD-II code B1795 indicates a problem with the low-beam headlamp circuit, specifically that there is an open circuit. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Visual Inspection:
• Check the headlamp assembly for any visible damage or corrosion.
• Inspect the wiring harness and connectors for frayed wires, loose connections, or corrosion.
• Ensure that the headlamp bulbs are properly seated in their sockets.
• Check the Headlamp Bulbs:
• Remove the low-beam headlamp bulbs and test them with a multimeter or replace them with known good bulbs to rule out a bulb failure.
• Test the Headlamp Circuit:
• Use a multimeter to check for voltage at the headlamp connector while the low beams are turned on. You should see battery voltage (typically around 12V).
• If there is no voltage, trace the wiring back to the fuse box and check for continuity.
• Inspect Fuses and Relays:
• Check the fuse associated with the low-beam headlamps. If it is blown, replace it and see if the problem persists.
• Test the relay for the low-beam headlamps (if applicable) to ensure it is functioning correctly.
• Check Ground Connections:
• Ensure that the ground connection for the headlamp circuit is secure and free of corrosion. A poor ground can cause an open circuit.
• Scan for Additional Codes:
• Use an OBD-II scanner to check for any other related trouble codes that may provide additional context for the issue.
• Inspect the Body Control Module (BCM):
• If all other components check out, the issue may lie within the BCM or the wiring leading to it. Check for any software updates or known issues with the BCM.
• Consult Wiring Diagrams:
• Refer to the vehicle’s wiring diagrams to trace the circuit and identify any other components that may be involved in the low-beam circuit.
• Perform a Continuity Test:
• With the vehicle off, perform a continuity test on the wiring from the headlamp connector back to the BCM or fuse box to ensure there are no breaks in the wire.
• Professional Diagnosis:
• If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who can perform more advanced diagnostics. By following these steps, you should be able to identify and resolve the issue causing the B1795 code.