B1604 – OBD-II DTC

OBD-II DTC B1604 – Lamp Anti-Theft Indicator Circuit Open

DTC B1604 meaning

DTC B1604 refers to a diagnostic trouble code indicating an issue with the Lamp Anti-Theft Indicator Circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the anti-theft indicator lamp circuit, which is responsible for signaling the status of the vehicle’s security system.

DTC B1604 symptoms

Common symptoms associated with DTC B1604 may include:

• The anti-theft indicator lamp not illuminating when the vehicle is armed or disarmed.
• Possible issues with the vehicle’s security system, such as failure to start or unexpected alarm activation.
• Other related warning lights on the dashboard may be illuminated.

DTC B1604 causes

Several factors can lead to the triggering of DTC B1604, including:

• A broken or damaged wire in the anti-theft indicator circuit.
• A faulty anti-theft indicator lamp.
• Issues with the vehicle’s body control module (BCM) or other related control modules.
• Corrosion or poor connections in the circuit.

DTC B1604 seriousness

The seriousness of DTC B1604 can vary. While it may not prevent the vehicle from operating, it can indicate potential issues with the anti-theft system that could lead to security vulnerabilities. It is advisable to address this code promptly to ensure the vehicle’s security features are functioning correctly.

How to diagnose DTC B1604

To diagnose DTC B1604, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1604 code.
2. Inspect the anti-theft indicator lamp for any visible damage or malfunction.
3. Check the wiring and connectors in the anti-theft indicator circuit for signs of wear, corrosion, or disconnection.
4. Test the continuity of the circuit using a multimeter.
5. Examine the body control module for any fault codes or issues.

How to fix DTC B1604 step-by-step instructions

To fix DTC B1604, follow these step-by-step instructions:

1. Confirm the DTC B1604 code using an OBD-II scanner.
2. Inspect the anti-theft indicator lamp and replace it if it is faulty.
3. Repair or replace any damaged wiring or connectors in the anti-theft indicator circuit.
4. Ensure all connections are secure and free from corrosion.
5. Check the body control module for proper operation and reprogram if necessary.
6. Clear the DTC using the OBD-II scanner and test the system to ensure the issue is resolved.

How to erase DTC B1604

To erase DTC B1604, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to check if the code reappears.

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