Airbags

B0033 — Second Row Left Frontal Airbag Stage 3 Deployment Circuit Fault

Severity: high Drive with care, to a shop

What B0033 means

B0033 means the airbag control module detected a problem in the circuit that controls stage 3 deployment of the second-row left frontal airbag. The module normally monitors the squib circuit resistance, and if it sees a fault it disables the circuit and turns on the airbag light. Exact naming and airbag location vary by manufacturer and equipment.

Symptoms

  • AIRBAG/SRS warning light on
  • Stored airbag fault codes
  • Light may be steady or flashing
  • Airbag system may be disabled

Possible causes

  1. Damaged wiring or corroded connector in the second-row left airbag circuit
  2. Loose or missing connector position assurance (CPA) retainer
  3. Faulty airbag inflator/squib or airbag module
  4. Faulty airbag control module
  5. Open circuit or short to ground or power after interior work or seat changes
  6. Damaged contacts under the seat or in the pillar

How to diagnose

  1. Scan all SRS codes with a tool that supports airbags and note whether the fault is current or history
  2. Ask about recent work: seat removal, trim repair, or a collision
  3. Disconnect the battery and wait the manufacturer's specified time before touching any SRS connector
  4. Inspect the airbag connectors, CPA retainers, corrosion, and pinched or stretched wires
  5. Test circuit continuity and resistance per the factory wiring diagram, never applying power to the squib
  6. Check the circuit for shorts to ground and to voltage
  7. If wiring is good, replace the suspect component as indicated by diagnostics
  8. Clear codes and verify the fault does not return

Common fixes

  • Repair or replace damaged wiring and connectors
  • Secure or replace the CPA retainer or connector
  • Replace the second-row left airbag or inflator
  • Replace or reprogram the airbag control module
  • Clean contacts and fix the cause of corrosion

Questions and answers

What does B0033 mean?

It is a fault in the control circuit for stage 3 of the second-row left frontal airbag. The SRS module sees an abnormal reading and may disable that airbag.

Can I drive with B0033?

Yes, but the airbag may not work in a crash. Fix it as soon as you can.

Can I check the airbag circuit myself?

You can visually inspect connectors with the battery disconnected. Electrical tests and part replacement are best left to a professional because of the risk of accidental deployment.

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.