B1797 – OBD-II DTC

OBD-II DTC B1797 – Lamp Headlamp Low-Beam Circuit Short To Ground

DTC B1797 meaning

DTC B1797 refers to a diagnostic trouble code indicating a short circuit in the low-beam headlamp circuit. This code is generated when the vehicle’s onboard diagnostic system detects that the low-beam headlamp circuit is grounded improperly, which can lead to malfunctioning of the headlamps.

DTC B1797 symptoms

Common symptoms associated with DTC B1797 may include:

• Low-beam headlamps not functioning
• Headlamp warning light illuminated on the dashboard
• Possible flickering or intermittent operation of the low-beam headlamps
• Increased electrical load on the vehicle’s electrical system

DTC B1797 causes

Several factors can lead to the occurrence of DTC B1797, including:

• Damaged wiring or connectors in the low-beam headlamp circuit
• Faulty headlamp relay
• Short circuit due to moisture or corrosion
• Defective headlamp assembly
• Issues with the vehicle’s body control module (BCM)

DTC B1797 seriousness

DTC B1797 is considered a serious issue as it directly affects the vehicle’s visibility during nighttime driving. Non-functioning low-beam headlamps can pose a safety risk to the driver and other road users. It is important to address this code promptly to ensure safe driving conditions.

How to diagnose DTC B1797

To diagnose DTC B1797, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the low-beam headlamp circuit wiring and connectors for damage or corrosion.
• Check the headlamp relay for proper operation.
• Test the headlamp assembly for any signs of failure.
• Examine the body control module for any faults or issues.

How to fix DTC B1797 step-by-step instructions

To fix DTC B1797, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect the wiring and connectors in the low-beam headlamp circuit for any visible damage.
3. If damage is found, repair or replace the affected wiring or connectors.
4. Test the headlamp relay and replace it if it is faulty.
5. Check the headlamp assembly for defects and replace it if necessary.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Test the low-beam headlamps to ensure they are functioning correctly.

How to erase DTC B1797

To erase DTC B1797, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the vehicle’s ignition without starting the engine.
• Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
• Confirm the action to clear the trouble codes.
• Disconnect the scanner and start the vehicle to verify that the code does not reappear.

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