DTC Code B0071 – What does this code mean?

<ul> <li><b>Air Bag Warning Light ON</b>: <p>The airbag warning light illuminates on the dashboard, indicating a potential issue with the airbag system. This is often linked to the <b>B0071</b> code, which signifies a problem with the passenger seat belt tension sensor circuit.</p></li> <li><b>Passenger Seat Belt Tension Sensor Malfunction</b>: <p>The passenger seat belt tension sensor may not function correctly, leading to improper detection of seat belt tension. This can be caused by a faulty sensor, damaged wiring, or a poor connection in the circuit.</p></li> <li><b>Airbag System Deactivation</b>: <p>Due to the malfunction in the seat belt tension sensor circuit, the airbag system may deactivate to prevent accidental deployment. This is a safety measure but can compromise passenger safety in the event of a collision.</p></li> </ul>

<ul><li>Faulty Passenger Seat Belt Retractor can lead to incorrect tension sensor readings.</li><li>An open or shorted harness in the Passenger Seat Belt Retractor can disrupt the sensor circuit.</li><li>Poor electrical connections in the Passenger Seat Belt Retractor circuit can cause intermittent sensor failures.</li><li>A malfunctioning Passenger Presence Module can incorrectly signal the seat belt tension sensor.</li></ul>

<ul> <li><b>Initial Inspection</b>: Inspect the passenger seat belt tension sensor and its wiring for any visible damage, corrosion, or disconnections.</li> <li><b>Check for DTC Variants</b>: Identify the specific variant of the B0071 code (03, 04, 07, or 08) to narrow down the diagnostic path.</li> <li><b>Voltage Below Threshold (B0071:03)</b>: Measure the voltage at the sensor connector. If the voltage is below the specified threshold, check for short circuits or faulty sensor.</li> <li><b>Circuit Open (B0071:04)</b>: Perform a continuity test on the sensor circuit. If the circuit is open, trace and repair any broken wires or connections.</li> <li><b>Voltage Above Threshold (B0071:07)</b>: Measure the voltage at the sensor connector. If the voltage is above the specified threshold, check for short to power or a faulty sensor.</li> <li><b>Voltage Performance Signal Invalid (B0071:08)</b>: Verify the sensor signal against manufacturer specifications. If the signal is invalid, replace the sensor.</li> <li><b>Clear DTC and Test</b>: After repairs, clear the DTC and perform a test drive to ensure the issue is resolved.</li></ul>

<p>The DTC code B0071 indicates an issue with the Passenger Seat Belt Tension Sensor Circuit. This is a critical safety component. <ul><li>Immediate action is required to diagnose and repair the sensor or its circuit.</li><li>Failure to address this issue can result in the passenger airbag not deploying correctly in an accident, increasing the risk of injury.</li></ul></p>