B1608 – Illuminated Entry Input Open Circuit

The ODBII code B1608 indicates that there is an open circuit in the illuminated entry system, which means the system is not receiving the expected signal from the input switch or sensor related to the vehicle’s entry lighting.

The severity of ODBII code B1608 is generally considered low.

Common Causes For: B1607 Illuminated Entry Input Circuit Failure

• Faulty door switch
• Damaged wiring or connectors
• Malfunctioning body control module (BCM)
• Poor ground connection
• Open circuit in the wiring harness
• Defective keyless entry system
• Issues with the vehicle’s security system

Common misdiagnosis for B1608 Illuminated Entry Input Open Circuit

• Faulty door switch
• Wiring issues
• Body control module (BCM) failure
• Malfunctioning keyless entry system
• Battery issues
• Ground connection problems
• Faulty interior lights
• Incorrectly programmed BCM settings

Common Troubleshooting Steps

The OBD-II code B1608 typically indicates an issue with the illuminated entry system, specifically an open circuit in the input signal. This can be related to the vehicle’s door switches, wiring, or the body control module (BCM). Here are some common troubleshooting steps to diagnose and resolve the issue:

• Check the Vehicle’s Manual: Refer to the vehicle’s service manual for specific information related to the B1608 code, including wiring diagrams and component locations.
• Inspect Door Switches:
• Check the door switches for proper operation. These switches are usually located in the door frame and are activated when the door is opened.
• Ensure that the switches are not stuck or damaged. If they are faulty, they may need to be replaced.
• Examine Wiring and Connectors:
• Inspect the wiring harnesses and connectors associated with the illuminated entry system for any signs of damage, corrosion, or loose connections.
• Pay special attention to the wiring that runs from the door switches to the BCM.
• Test the Circuit:
• Use a multimeter to test the continuity of the circuit from the door switch to the BCM. If there is an open circuit, trace the wiring to find the break.
• Check for voltage at the door switch when the door is opened. If there is no voltage, the issue may be upstream in the wiring or the BCM.
• Check the Body Control Module (BCM):
• If the door switches and wiring are functioning correctly, the issue may lie with the BCM itself. Check for any fault codes stored in the BCM and perform any necessary tests as outlined in the service manual.
• If the BCM is suspected to be faulty, it may need to be reprogrammed or replaced.
• Clear the Code and Test Drive:
• After performing repairs, clear the B1608 code using an OBD-II scanner and take the vehicle for a test drive to see if the code reappears.
• Consult a Professional:
• If the issue persists after performing these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the B1608 code.