B1647 – Seat Driver Recline Forward Circuit Failure

The ODBII code B1647 indicates a malfunction in the driver seat recline forward circuit, suggesting a failure in the electrical system or components related to the seat’s recline function.

The severity of ODBII code B1647 is generally considered moderate.

Common Causes For: B1646 Mirror Passenger Right Circuit Short To Ground

• Faulty seat recline motor
• Damaged wiring or connectors
• Failed seat position sensor
• Short circuit in the circuit
• Open circuit in the wiring
• Malfunctioning body control module (BCM)
• Corrosion or poor connections in the electrical system

Common misdiagnosis for B1647 Seat Driver Recline Forward Circuit Failure

• Faulty seat motor
• Wiring issues or shorts
• Malfunctioning seat switch
• Body control module (BCM) failure
• Connector problems or corrosion
• Power supply issues
• Faulty ground connection

Common Troubleshooting Steps

The OBD-II code B1647 indicates a “Seat Driver Recline Forward Circuit Failure.” This code is typically associated with issues in the seat recline mechanism, which can be caused by electrical problems, mechanical failures, or issues with the seat control module. Here are some common troubleshooting steps to diagnose and potentially resolve the issue:

• Visual Inspection: **Wiring and Connectors: Check the wiring harness and connectors related to the seat recline motor for any signs of damage, corrosion, or loose connections.
• **Seat Mechanism: Inspect the seat recline mechanism for any physical obstructions or mechanical failures.
• Check the Seat Control Module: **Module Functionality: Ensure that the seat control module is functioning properly. If you have access to a scan tool, check for any additional codes that may indicate a problem with the module.
• **Reprogramming: In some cases, the module may need to be reprogrammed or reset.
• Test the Recline Motor: **Motor Operation: Use a multimeter to test the recline motor for continuity. If the motor is not functioning, it may need to be replaced.
• **Power Supply: Check if the motor is receiving power when the recline switch is activated. If not, there may be an issue with the switch or wiring.
• Inspect the Recline Switch: **Switch Functionality: Test the seat recline switch for proper operation. A faulty switch can prevent the motor from receiving the signal to operate.
• **Wiring to Switch: Check the wiring leading to the switch for any damage or disconnections.
• Check for Ground Issues: **Ground Connections: Ensure that all ground connections related to the seat system are secure and free of corrosion. A poor ground can lead to circuit failures.
• Scan for Additional Codes: **Diagnostic Scan: Use an OBD-II scanner to check for any other related trouble codes that may provide more context to the issue.
• Consult Wiring Diagrams: **Wiring Diagrams: Refer to the vehicle’s service manual for wiring diagrams to trace the circuit and identify any potential issues.
• Perform a Reset: **Clear Codes: After addressing any identified issues, clear the trouble codes and test the system to see if the code reappears.
• Professional Diagnosis: If the issue persists after performing these steps, consider seeking help from a professional mechanic or automotive technician who has experience with electrical systems and can perform more advanced diagnostics. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the B1647 code. Always ensure safety precautions are taken when working with electrical components in vehicles.