B1690 – OBD-II DTC

OBD-II DTC B1690 – Autolamp Delay Circuit Open

DTC B1690 meaning

DTC B1690 refers to a diagnostic trouble code indicating an issue with the autolamp delay circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the autolamp delay feature, which is responsible for controlling the automatic operation of the vehicle’s exterior lights based on ambient light conditions.

DTC B1690 symptoms

Common symptoms associated with DTC B1690 may include:

• Exterior lights not functioning as intended
• Autolamp feature not activating
• Dashboard warning lights illuminated
• Inconsistent lighting behavior

DTC B1690 causes

The causes of DTC B1690 can vary, but typical reasons include:

• Open circuit in the autolamp delay wiring
• Faulty autolamp delay relay
• Defective body control module (BCM)
• Corroded or damaged connectors
• Short circuits in the wiring harness

DTC B1690 seriousness

DTC B1690 is considered a moderate issue. While it may not immediately affect the vehicle’s drivability, it can lead to safety concerns due to improper lighting. If the exterior lights do not function correctly, it can reduce visibility during nighttime driving or adverse weather conditions.

How to diagnose DTC B1690

To diagnose DTC B1690, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1690 code.
2. Inspect the vehicle’s wiring and connectors related to the autolamp delay circuit for any visible damage or corrosion.
3. Test the continuity of the wiring to ensure there are no open circuits.
4. Check the autolamp delay relay for proper operation.
5. Examine the body control module for any faults or issues.

How to fix DTC B1690 step-by-step instructions

To fix DTC B1690, follow these steps:

1. Identify and repair any damaged wiring or connectors in the autolamp delay circuit.
2. Replace the autolamp delay relay if it is found to be faulty.
3. Test and, if necessary, replace the body control module.
4. Ensure all connections are secure and free from corrosion.
5. Clear the DTC using an OBD-II scanner and test the system to confirm the issue is resolved.

How to erase DTC B1690

To erase DTC B1690, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the vehicle’s ignition without starting the engine.
3. Access the diagnostic trouble codes menu on the scanner.
4. Select the option to clear or erase codes.
5. Confirm the action and wait for the scanner to indicate that the codes have been cleared.

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