Airbags

B009B — Left Side Restraints Sensor 5 Fault (Subfault)

Severity: medium Safe to drive

What B009B means

The supplemental restraint system (SRS) control module runs self-tests and detected a fault in the circuit or the sensor itself for left side restraints sensor 5. This is typically a side impact or door pressure sensor, or a related component. With this fault, the left side restraints may not deploy correctly in a crash.

Symptoms

  • Airbag (SRS) warning light is on
  • Seat belt warning or indicator behaves abnormally
  • Scan tool shows B009B stored
  • Code returns after being cleared

Possible causes

  1. Failed left side restraints sensor 5
  2. Damaged wiring or poor connection at the sensor connector
  3. Corrosion or loose terminals after body, door or seat work
  4. Faulty SRS control module (less common)

How to diagnose

  1. Read all SRS codes and review freeze frame data to see if the fault is current or intermittent
  2. Find the sensor 5 location on the left side using the vehicle wiring diagram
  3. Inspect the sensor connector and harness for damage, moisture, corrosion and pinching
  4. Ask about recent collision repair or removal of door trim or seats on the left side
  5. Check circuit resistance and supply per the manufacturer procedure; do not probe airbag circuits with an ordinary meter without instructions
  6. Following the manufacturer's battery disconnect wait time, confirm connectors are fully seated
  7. Swap in a known good sensor and see if the code clears

Common fixes

  • Replace left side restraints sensor 5
  • Repair or replace damaged wiring and connectors
  • Clean terminals and restore a solid connection
  • Repair or replace the SRS control module if confirmed faulty

Questions and answers

What does B009B mean?

The SRS module found a fault with left side restraints sensor 5. The most common causes are the sensor itself or its wiring and connector.

Can I drive with B009B?

The car will drive normally, but left side airbags or pretensioners may not deploy in a crash. Don't put off the repair.

Can I just clear B009B?

Clearing only turns the light off for a while. If the fault is still there the code will return and the system stays unreliable.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.