B1605 – Lamp Anti-Theft Indicator Circuit Short To Battery

The ODBII code B1605 indicates a short circuit in the anti-theft indicator lamp circuit, causing it to be continuously powered by the battery.

The severity of ODBII code B1605 is moderate.

Common Causes For: B1604 Lamp Anti-Theft Indicator Circuit Open

• Shorted wiring in the anti-theft indicator circuit.
• Faulty anti-theft indicator lamp.
• Malfunctioning body control module (BCM).
• Corroded or damaged connectors.
• Incorrectly installed aftermarket alarm system.
• Grounding issues in the circuit.

Common misdiagnosis for B1605 Lamp Anti-Theft Indicator Circuit Short To Battery

• Faulty anti-theft module
• Shorted wiring harness
• Defective ignition switch
• Malfunctioning body control module (BCM)
• Bad ground connection
• Incorrectly installed aftermarket alarm system
• Faulty key fob or transponder
• Defective battery or poor battery connections

Common Troubleshooting Steps

When dealing with OBD-II code B1605, which indicates a “Lamp Anti-Theft Indicator Circuit Short To Battery,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check the Vehicle’s Manual: Refer to the vehicle’s service manual for specific information regarding the anti-theft system and the wiring diagrams related to the indicator circuit.
• Visual Inspection: Inspect the wiring and connectors associated with the anti-theft indicator circuit. Look for:
• Damaged, frayed, or corroded wires.
• Loose or disconnected connectors.
• Signs of short circuits or grounding issues.
• Check the Anti-Theft Indicator Bulb: If applicable, check the anti-theft indicator bulb for proper operation. A burnt-out bulb can sometimes trigger false codes.
• Test the Circuit: Use a multimeter to check for continuity in the anti-theft indicator circuit.
• Measure the voltage at the indicator circuit to see if it is receiving the correct voltage. A short to battery may cause the circuit to read higher than expected.
• Inspect the Anti-Theft Module: If the vehicle is equipped with an anti-theft module, inspect it for any signs of damage or malfunction.
• Check for any stored trouble codes in the module that may provide additional context.
• Check for Short Circuits: Use a multimeter to check for shorts to ground or battery in the wiring harness.
• Disconnect the battery and perform a resistance test between the circuit and ground.
• Clear the Code: After performing inspections and repairs, clear the trouble code using an OBD-II scanner.
• Monitor the system to see if the code returns.
• Test Drive the Vehicle: After clearing the code, take the vehicle for a test drive to see if the code reappears. This can help confirm whether the issue has been resolved.
• Consult a Professional: If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or an automotive electrician for further diagnosis.Additional Tips: – Always ensure that the vehicle’s battery is disconnected before working on electrical components to avoid any accidental shorts or shocks. – Document any changes or repairs made during the troubleshooting process for future reference. By following these steps, you should be able to identify and resolve the issue related to the B1605 code.