B1587 – OBD-II DTC

OBD-II DTC B1587 – Autolamp Delay Increase Circuit Failure

DTC B1587 meaning

DTC B1587 refers to a fault in the Autolamp Delay Increase Circuit. This diagnostic trouble code indicates that there is a malfunction in the system responsible for controlling the delay of the vehicle’s automatic lighting features. The Autolamp system is designed to automatically turn on and off the vehicle’s lights based on ambient light conditions, and the delay feature allows for a specified time before the lights turn off after the vehicle is exited.

DTC B1587 symptoms

Common symptoms associated with DTC B1587 may include:

• Automatic lights not functioning as intended
• Lights staying on longer than expected
• Lights turning off too quickly
• Dashboard warning lights illuminated

DTC B1587 causes

Several factors can lead to the occurrence of DTC B1587, including:

• Faulty wiring or connectors in the Autolamp delay circuit
• Defective Autolamp control module
• Corrosion or damage to electrical components
• Software issues within the vehicle’s control systems

DTC B1587 seriousness

The seriousness of DTC B1587 can vary. While it may not pose an immediate safety risk, it can lead to issues with visibility if the lights do not operate correctly. Additionally, it may indicate underlying electrical problems that could affect other systems in the vehicle. Therefore, it is advisable to address this code promptly to ensure proper vehicle operation.

How to diagnose DTC B1587

To diagnose DTC B1587, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the wiring and connectors related to the Autolamp delay circuit for any visible damage or corrosion.
3. Check the Autolamp control module for proper operation.
4. Test the circuit for continuity and proper voltage using a multimeter.
5. Review any related codes that may provide additional context for the issue.

How to fix DTC B1587 step-by-step instructions

To fix DTC B1587, follow these step-by-step instructions:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and repair any damaged wiring or connectors found during diagnosis.
3. Replace the Autolamp control module if it is determined to be faulty.
4. Ensure all connections are secure and free of corrosion.
5. Recheck the system by performing a function test of the Autolamp feature.
6. Re-scan the vehicle to ensure the code does not return.

How to erase DTC B1587

To erase DTC B1587, 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 verify that the code has been cleared.

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