B0033

Code

Generic B — Body

Second Row Left Frontal Stage 3 Deployment Control

Brand: Generic

Type: B — Body

Views: UK: 33 EN: 51 RU: 28

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or short in the second-row left frontal stage 3 squib (inflator) wiring
Poor or corroded connector or pin at the seat or harness
Damaged seat wiring (chafing, cuts, pinched harness) or connector
Faulty airbag squib (stage 3 element) or pretensioner component
Faulty SRS/airbag control module or driver (control unit)
Intermittent connection due to seat movement, connector seating, or corrosion

Symptoms

Airbag / SRS warning lamp illuminated on dash
Possible disablement of second-row left frontal stage deployment
Stored DTC B0033 in airbag control module
Possible related communication or additional SRS codes if module is affected

What to check

Use a scan tool to read DTC B0033 and any related SRS codes; record freeze frame and pending codes
Visually inspect second-row left seat, connectors, and harness for damage, corrosion, or deformation
Inspect for signs of prior collision repair in the area (patched harness, replaced components)
Check connector pins for corrosion, bent pins, or terminal loss
Verify battery voltage and proper ground integrity before and during diagnosis
Confirm you can communicate with the airbag control module using a suitable scan tool

Signal parameters

Typical squib resistance (after disconnecting connector): generally around ~1–3 ohms for pyrotechnic squibs; values much higher (open/infinite) or much lower (
Continuity: closed (low ohms) between squib terminals when intact; open indicates broken circuit
Short to ground: near 0 ohms between squib circuit and chassis ground indicates short
Module communication: airbag control module should respond to diagnostic tool; loss of comm suggests module or bus issue

Diagnostic algorithm

Safety first — follow manufacturer SRS safety procedures before any inspection or measurement (disable SRS power, disconnect battery per manufacturer, and wait the specified time).
Connect a capable scan tool, confirm B0033 is current, record freeze-frame data and any related codes.
Perform a careful visual inspection of the second-row left seat area, harness routing, connectors, and connector locks for damage, corrosion, or water ingress.
With SRS power disabled and following safety procedure, disconnect the squib connector at the seat/module and measure resistance of the stage 3 squib circuit at the connector. Compare to expected range (~1–3 ohms).
If open or high resistance: trace harness for breaks, test continuity to the airbag control module connector. Repair damaged wiring/connectors as found.
If very low resistance (short): isolate circuit sections and test for short to ground or battery; repair insulation or replace shorted component.

Likely causes

Wiring open/infinite resistance in the stage 3 squib circuit
Short to ground or battery on the squib circuit (very low resistance)
Corroded or loose connector at the second-row left seat or airbag module
Failed squib (internal short/open within the inflator firing element)
Airbag control module detecting circuit fault or incorrect calibration

Fault status

⚠️ Status

Stored DTC B0033 — Second Row Left Frontal Stage 3 Deployment Control. SRS warning lamp likely active; affected deployment stage may be disabled until fault is corrected.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.5 - 3.0 hours