B1592 – Autolamp Delay Decrease Circuit Open

The ODBII code B1592 indicates that there is an open circuit in the autolamp delay decrease circuit, which affects the operation of the automatic headlight delay feature.

The severity of ODBII code B1592 is generally considered moderate.

Common Causes For: B1591 Autolamp Delay Decrease Circuit Failure

• Open circuit in the autolamp delay wiring
• Faulty autolamp delay relay
• Defective body control module (BCM)
• Poor ground connection
• Damaged or corroded connectors
• Faulty autolamp switch
• Short circuit in the wiring harness

Common misdiagnosis for B1592 Autolamp Delay Decrease Circuit Open

• Faulty headlight switch
• Malfunctioning body control module (BCM)
• Wiring issues or shorts in the circuit
• Defective autolamp sensor
• Incorrectly diagnosed battery or charging system problems
• Issues with the vehicle’s lighting control module
• Faulty relay or fuse related to the lighting system

Common Troubleshooting Steps

The OBD-II code B1592 refers to a problem with the autolamp delay decrease circuit, indicating that there is an open circuit in the system. Here are some common troubleshooting steps to diagnose and potentially resolve this issue:

• Check the Vehicle’s Manual: Refer to the vehicle’s service manual for specific information about the autolamp system and the wiring diagrams. This will help you understand the circuit layout and components involved.
• Visual Inspection:
• Inspect the wiring and connectors associated with the autolamp system for any visible damage, corrosion, or loose connections.
• Look for frayed wires, broken connectors, or any signs of wear that could lead to an open circuit.
• Check Fuses:
• Locate the fuse box and check for any blown fuses related to the lighting or autolamp system. Replace any blown fuses and see if the code clears.
• Test the Circuit:
• Use a multimeter to test the continuity of the wires in the autolamp delay decrease circuit. Check for any breaks or opens in the wiring.
• Measure the voltage at the relevant connectors to ensure that power is being supplied to the circuit.
• Inspect the Autolamp Module:
• If applicable, check the autolamp control module for any faults. This may involve testing the module’s inputs and outputs.
• If the module is suspected to be faulty, it may need to be replaced.
• Check for Short Circuits:
• While you are testing the circuit, also check for any short circuits that may be affecting the autolamp system.
• Scan for Additional Codes:
• Use an OBD-II scanner to check for any other related trouble codes that may provide additional context or indicate other issues in the system.
• Clear the Code:
• After performing the above checks and repairs, clear the trouble code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult a Professional:
• If you are unable to identify or resolve the issue, it may be best to consult a professional mechanic or technician who has experience with automotive electrical systems. By following these steps, you should be able to diagnose and potentially fix the issue related to the B1592 code. Always ensure safety precautions are taken when working with electrical systems in vehicles.