Airbags

B0031 — Second Row Left Frontal Stage 1 Deployment Control Circuit Fault

Severity: high Drive with care, to a shop

What B0031 means

The SRS control module constantly monitors the resistance and voltage of each squib circuit. B0031 means the stage 1 deployment circuit for the second row left frontal restraint (airbag or belt pretensioner) is out of range, from an open, a short or a poor connection. While the fault exists, that restraint may not deploy in a crash.

Symptoms

  • SRS or airbag warning light is on
  • SRS module has stored the code
  • Possible seat belt pretensioner or airbag circuit problem
  • Light may come and go when the seat is moved or the car hits bumps

Possible causes

  1. Open or shorted SRS wiring harness
  2. Corroded or loose connector, or poor ground
  3. Faulty airbag or pretensioner squib
  4. Faulty SRS control module
  5. Circuit voltage too low or too high
  6. Harness damage under the seat or at the pillar

How to diagnose

  1. Scan all SRS codes and note the freeze frame data
  2. Disconnect the battery and wait several minutes so the SRS capacitors discharge
  3. Inspect connectors and harness under the front and rear seats, at the pillar and at the belt anchor
  4. Check connector locks and terminals for corrosion or damage
  5. Test the circuit for opens and shorts to ground or power, without applying voltage to the squib
  6. Substitute a known good part only as the manufacturer's procedure allows
  7. Clear the code and see if it returns

Common fixes

  • Repair or replace damaged wiring and connectors
  • Replace the faulty pretensioner or airbag module
  • Replace or reprogram the SRS control module
  • Clean and secure terminals and grounds

Questions and answers

What does B0031 mean?

The SRS module found a fault in the stage 1 deployment circuit of the second row left frontal restraint. The usual culprits are wiring, a connector or the restraint itself.

Can I test the airbag circuit myself?

Only with the battery disconnected and following the service procedure. Never apply voltage to a squib or probe it with a standard meter in a live circuit, as it can deploy. Leave it to a professional if unsure.

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.