B1796 – Lamp Headlamp Low-Beam Circuit Short To Battery

The ODBII code B1796 indicates a short circuit in the low-beam headlamp circuit, meaning the circuit is receiving power directly from the battery instead of through the intended control system.

The severity of ODBII code B1796 is moderate to high.

Common Causes For: B1795 Lamp Headlamp Low-Beam Circuit Open

• Shorted wiring in the low-beam circuit
• Faulty headlight bulb
• Corroded or damaged connectors
• Malfunctioning headlight relay
• Faulty body control module (BCM)
• Incorrectly installed or damaged fuse
• Grounding issues in the circuit

Common misdiagnosis for B1796 Lamp Headlamp Low-Beam Circuit Short To Battery

• Faulty headlight bulb
• Defective headlight relay
• Wiring harness issues
• Malfunctioning body control module (BCM)
• Incorrectly installed or damaged connectors
• Shorted or damaged wiring
• Faulty switch or control stalk
• Grounding issues

Common Troubleshooting Steps

The OBD-II code B1796 indicates a problem with the low-beam headlamp circuit, specifically a short to battery. 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 signs of wear.
• Look for any signs of moisture or dirt that could affect the electrical connections.
• Check the Headlamp Bulb:
• Remove the low-beam headlamp bulb and inspect it for damage. Replace it if necessary.
• Ensure that the bulb is properly seated in the socket.
• Test the Headlamp Circuit:
• Use a multimeter to check for voltage at the headlamp connector. With the headlight switch on, you should see battery voltage.
• If there is no voltage, trace the wiring back to the switch and check for continuity.
• Inspect the Ground Connection:
• Ensure that the ground connection for the headlamp is secure and free of corrosion. A poor ground can cause electrical issues.
• Check for Shorts:
• Inspect the wiring for any signs of a short circuit. This can include wires that are pinched, frayed, or touching metal surfaces.
• Use a multimeter to check for continuity between the low-beam circuit and ground. If there is continuity when the circuit should be open, there may be a short.
• Examine the Headlight Switch:
• Test the headlight switch for proper operation. A faulty switch can cause incorrect signals to be sent to the headlamp circuit.
• Check the Relay and Fuses:
• Inspect the headlamp relay and fuses related to the low-beam circuit. Replace any blown fuses and test the relay for proper operation.
• Scan for Additional Codes:
• Use an OBD-II scanner to check for any additional trouble codes that may provide more context for the issue.
• Consult Wiring Diagrams:
• Refer to the vehicle’s wiring diagrams to understand the circuit layout and identify any other components that may be involved.
• Professional Diagnosis:
• If the issue persists after performing these steps, consider seeking help from a professional mechanic or automotive technician who can perform more advanced diagnostics. By following these steps, you should be able to identify and resolve the issue related to the B1796 code.