OBD Guide

B2909

Belt Tension Sensor Fault

B2909 is an OBD-II diagnostic trouble code meaning: Belt Tension Sensor Fault. Common causes: belt tension sensor malfunction, broken or damaged wiring harness to the sensor. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–167 (est.)

Symptoms

  • Airbag light is on
  • Security error message on dashboard
  • Incorrect operation of seat belt pretensioners

Causes

  • Belt tension sensor malfunction
  • Broken or damaged wiring harness to the sensor
  • Short circuit in the sensor circuit
  • Problems with the security control unit

How to Fix

  1. Conduct diagnostics of the passive safety system
  2. Check the integrity of the wiring harness to the sensor
  3. Check the resistance of the belt tension sensor
  4. If necessary, replace the belt tension sensor
  5. Reset errors and check system operation

Related codes

FAQ

What does the B2909 code mean?

B2909 is an OBD-II diagnostic trouble code that indicates: Belt Tension Sensor Fault

What causes a B2909 error code?

The most common causes of B2909 include: Belt tension sensor malfunction; Broken or damaged wiring harness to the sensor; Short circuit in the sensor circuit; Problems with the security control unit.

How do I fix a B2909 diagnostic trouble code?

To fix B2909: Conduct diagnostics of the passive safety system. Check the integrity of the wiring harness to the sensor. Check the resistance of the belt tension sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B2909?

Do not drive — repair immediately

How much does it cost to fix B2909?

The estimated repair cost for B2909 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat