OBD-II DTC B1689 – Autolamp Delay Circuit Failure
DTC B1689 meaning
DTC B1689 refers to a fault in the autolamp delay circuit, which is responsible for controlling the automatic headlight feature in vehicles. This code indicates that there is a malfunction in the circuit that manages the delay function of the autolamps, which may prevent the headlights from turning off after a specified time or may cause them to operate incorrectly.
DTC B1689 symptoms
Common symptoms associated with DTC B1689 may include:
- Headlights not turning off after the delay period.
- Headlights remaining on indefinitely.
- Inconsistent operation of the autolamp feature.
- Dashboard warning lights illuminated.
DTC B1689 causes
Several factors can lead to the occurrence of DTC B1689, including:
- Faulty autolamp relay.
- Wiring issues, such as shorts or open circuits.
- Defective body control module (BCM).
- Corroded or loose connectors in the autolamp circuit.
DTC B1689 seriousness
The seriousness of DTC B1689 can vary. While it may not pose an immediate safety risk, it can lead to battery drain if the headlights remain on for extended periods. Additionally, it can affect visibility during nighttime driving, making it important to address the issue promptly.
How to diagnose DTC B1689
To diagnose DTC B1689, follow these steps:
- Use an OBD-II scanner to confirm the presence of the code.
- Inspect the autolamp relay for proper operation.
- Check the wiring and connectors for damage or corrosion.
- Test the body control module for faults.
- Perform a visual inspection of the autolamp circuit.
How to fix DTC B1689 step-by-step instructions
To fix DTC B1689, follow these steps:
- Replace the faulty autolamp relay if necessary.
- Repair or replace damaged wiring and connectors.
- Test and replace the body control module if it is found to be defective.
- Clear any corrosion from connectors and ensure they are securely fastened.
- Recheck the system to ensure the issue is resolved.
How to erase DTC B1689
To erase DTC B1689, follow these steps:
- Connect an OBD-II scanner to the vehicle’s diagnostic port.
- Access the trouble codes menu on the scanner.
- Select the option to clear or erase codes.
- Confirm the action and wait for the scanner to complete the process.
- Disconnect the scanner and perform a test drive to ensure the code does not return.
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