Damaged or disconnected wiring harness at the second-row right seat, often from seat movement or cargo; Corroded or loose electrical connector at the stage 3 airbag inflator; Open or shorted stage 3 airbag inflator squib; Faulty restraint control module (RCM) internal driver circuit; Water intrusion or physical damage to the seat wiring from spills or cargo; Aftermarket seat covers or accessories pinching the harness

DTC codes / B00xx · Airbags, seats, doors, lights and comfort systems / B003B

B003BSecond Row Right Frontal Stage 3 Deployment Control

Q: What does code B003B mean?

Second Row Right Frontal Stage 3 Deployment Control. B003B indicates that the restraint control module (RCM) has detected a fault in the deployment circuit for the second-row right frontal airbag, stage 3. The module monitors the circuit's resistance and continuity and sets this code when the signal falls outside the expected range, which can prevent that airbag stage from deploying in a crash.

B003B indicates that the restraint control module (RCM) has detected a fault in the deployment circuit for the second-row right frontal airbag, stage 3. The module monitors the circuit's resistance and continuity and sets this code when the signal falls outside the expected range, which can prevent that airbag stage from deploying in a crash.

SystemBody

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaAirbags, seats, doors, lights and comfort systems

Symptoms you may notice

Airbag warning light illuminated on the instrument cluster
Often no symptoms besides the warning light
Passenger airbag status indicator may show 'off' or 'service' for the second-row right position
Supplemental restraint system (SRS) may be disabled for that seating position
In some vehicles, a chime or message center alert about the restraint system

Common causes, most likely first

Damaged or disconnected wiring harness at the second-row right seat, often from seat movement or cargo
Corroded or loose electrical connector at the stage 3 airbag inflator
Open or shorted stage 3 airbag inflator squib
Faulty restraint control module (RCM) internal driver circuit
Water intrusion or physical damage to the seat wiring from spills or cargo
Aftermarket seat covers or accessories pinching the harness

How to diagnose and fix it

Inspect the second-row right seat wiring harness and connectors for damage, corrosion, or loose pins
Disconnect the battery and wait for the recommended time, then check the stage 3 airbag connector for proper seating and terminal tension
Measure the resistance of the stage 3 airbag squib with a digital multimeter and compare to the manufacturer's specification
Check for continuity and shorts to ground or power on the circuit between the RCM and the airbag connector
If the circuit tests good, substitute a known-good airbag or use a simulator to isolate the RCM
Repair or replace damaged wiring, connectors, or the airbag inflator as needed
Clear the code and verify the repair with a scan tool and by cycling the ignition

Before you replace the airbag module

Seat movement and cargo loading frequently damage the second-row right harness, so inspect the wiring under the seat before condemning the airbag.
A stage 3 code does not always mean the airbag is defective; a poor connection at the yellow SRS connector can set the same code.
Aftermarket seat covers or objects stored under the seat can pinch or stress the harness, causing intermittent faults.
The RCM may set this code if battery voltage was low during a previous start, so check for related low-voltage codes before replacing parts.
Always follow the manufacturer's procedure for disabling the SRS before probing airbag circuits to avoid accidental deployment.

Can I keep driving with B003B?

The vehicle remains driveable, but the second-row right frontal airbag may not deploy in a crash, so avoid carrying passengers in that seat until the fault is repaired. Have the system diagnosed promptly to restore full restraint protection.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.