Passenger Frontal Stage 2 Deployment Control
What does B0004 mean?
The B0004 code means the vehicle's onboard diagnostic system has detected: Passenger Frontal Stage 2 Deployment Control. This is a critical severity code.
Common Symptoms
- SRS warning light on dashboard
- Airbag malfunction indicator illuminated
- Passenger airbag second stage disabled
- Warning chime active
- Potential inspection failure
Probable Causes (Ranked by Likelihood)
- Faulty stage 2 squib circuit in passenger airbag Very High
- Damaged wiring harness under dashboard High
- Corroded connector at passenger airbag module Moderate
- SRS control module malfunction Moderate
- Aftermarket dashboard modification interfering with wiring Low
Step-by-Step Diagnostic Procedure
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Pull all SRS DTCs with a compatible scanner
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Measure stage 2 squib resistance at passenger airbag connector
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Inspect wiring harness routing under dashboard for damage
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Check all SRS connectors for proper seating and corrosion
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Test SRS module outputs for proper voltage
Frequently Asked Questions
What is a stage 2 airbag squib?
A squib is the igniter that triggers airbag inflation. Stage 2 squibs provide additional deployment force during severe impacts for enhanced occupant protection.
Could this be caused by a previous accident?
Yes. If airbag components were not properly replaced or repaired after a prior collision, stage 2 circuits may have latent damage.
How long does the repair take?
Depending on the cause, repairs can take 1 to 4 hours. Replacing the airbag module itself is usually about 1-2 hours of labor.