B1656 – OBD-II DTC

OBD-II DTC B1656 – Seat Driver Rear Up Circuit Open

DTC B1656 meaning

DTC B1656 refers to a diagnostic trouble code indicating an issue with the seat driver rear up circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. Specifically, B1656 suggests that there is an open circuit in the electrical path that controls the upward movement of the driver’s rear seat. This can prevent the seat from adjusting properly, affecting comfort and safety.

DTC B1656 symptoms

Common symptoms associated with DTC B1656 may include:

• The driver’s rear seat not moving up or down.
• Intermittent or complete loss of seat adjustment functionality.
• Warning lights illuminated on the dashboard related to seat adjustments.
• Possible related codes stored in the OBD-II system.

DTC B1656 causes

Several factors can lead to the triggering of DTC B1656, including:

• A broken or frayed wire in the seat adjustment circuit.
• A faulty seat motor that controls the upward movement.
• Corroded or loose electrical connectors.
• Issues with the seat control module or switch.
• Faulty ground connections affecting the circuit.

DTC B1656 seriousness

The seriousness of DTC B1656 can vary based on the specific vehicle and its use. However, it is generally considered a moderate issue because:

• It affects the adjustability of the driver’s seat, which can impact driving comfort and ergonomics.
• It may lead to further electrical issues if not addressed.
• While it may not immediately affect vehicle safety, it can become a concern if the seat position is not optimal for safe driving.

How to diagnose DTC B1656

To diagnose DTC B1656, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1656 code.
2. Inspect the seat adjustment wiring for visible damage or disconnections.
3. Check the electrical connectors for corrosion or looseness.
4. Test the seat motor for functionality using a multimeter.
5. Examine the seat control module and switch for proper operation.
6. Clear the code and perform a seat adjustment test to see if the code reappears.

How to fix DTC B1656 step-by-step instructions

To fix DTC B1656, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Inspect the wiring harness for the driver’s rear seat adjustment for any signs of damage.
3. Repair or replace any damaged wires or connectors found during the inspection.
4. Test the seat motor by applying direct power to see if it operates correctly.
5. If the motor is faulty, replace it with a new one.
6. Check the seat control module and switch for proper operation replace if necessary.
7. Reconnect the battery and clear the DTC using an OBD-II scanner.
8. Test the seat adjustment functionality to ensure the issue is resolved.

Recommended tools for OBD-II diagnostics

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