B004B medium Severity

B004B: Third Row Right Frontal Stage 3 Deployment Control (Subfault)

May illuminate airbag/SRS warning; does not directly affect engine or drivability but compromises safety system

Overview

OBD‑II code B004B indicates a fault in the Supplemental Restraint System related to the third row right frontal airbag deployment control stage 3; requires SRS system diagnostics.

Common Symptoms

  • Airbag/SRS warning light on dashboard
  • Stored code B004B in airbag module
  • Possible loss of third row right frontal airbag deployment readiness

Most Common Causes

Faulty wiring harness or connector to third row right frontal airbag circuit medium

Wiring short to ground or power can trigger subfault reports in deployment control circuits. Evidence from generic subcode definitions suggests wiring harness issues. (Referenced details for wiring faults but specific forum data limited)

Defective airbag deployment control circuit/module medium

Internal failure in deployment control or sensor could prompt B004B; verify component integrity.

Sensor fault in SRS (impact or deployment decision sensor) medium

Sensor malfunction affecting deployment logic can set subfault code.

Diagnostic Steps

  1. Connect a professional SRS/Airbag scan tool and retrieve full DTC list
    Expected: Confirm presence of B004B and any related SRS codes
    Interpretation: Multiple airbag codes may indicate broader SRS issues beyond single circuit.
  2. Visually inspect wiring and connectors to the third row right frontal airbag and related SRS sensors
    Expected: Look for breaks, corrosion, connector damage, or exposed wires
    Interpretation: Damaged or poor connections often cause subfault codes in SRS deployment circuits.
  3. Measure continuity/resistance of airbag squib and deployment control circuit
    Expected: Resistance values should be within manufacturer specs (often very low ohms)
    Interpretation: High resistance or open circuits point to wiring or component failure.
  4. Test SRS control module internal diagnostics or consider reprogramming/flash update
    Expected: Module should not report internal errors; crash data memory may need clearing
    Interpretation: Persistent faults in module logic may require professional SRS module repair or replacement.

Repair Solutions

Repair or replace damaged wiring/connectors in third row right frontal SRS circuit medium
Estimated Cost: $100 - $500

Costs vary by vehicle and labor rates; airbag wiring repairs require careful handling of SRS system.

Replace faulty airbag deployment control module or sensor hard
Estimated Cost: $300 - $1500

Component cost and programming may increase total; requires professional SRS diagnostic tools.

Clear crash data and reset SRS module after repair medium
Estimated Cost: $50 - $200

Must ensure vehicle safety before clearing codes; improper clearing without fix is unsafe.

Common Misdiagnoses

Avoid these common diagnostic mistakes:

  • Assuming B004B is unrelated to SRS when only engine codes are scanned
  • Clearing the code without inspecting wiring or component health

Frequently Asked Questions

What does a B004B diagnostic trouble code signify?

The B004B code stands for Third Row Right Frontal Stage 3 Deployment Control (Subfault). This generally indicates an issue with the Sensors system.

Can B004B cause engine damage?

The B004B code is considered medium severity. May illuminate airbag/SRS warning; does not directly affect engine or drivability but compromises safety system

What are the symptoms of B004B?

Drivers often report: Airbag/SRS warning light on dashboard, Stored code B004B in airbag module, Possible loss of third row right frontal airbag deployment readiness when this code is present.

What causes the B004B code?

This code is frequently triggered by: Faulty wiring harness or connector to third row right frontal airbag circuit, Defective airbag deployment control circuit/module, Sensor fault in SRS (impact or deployment decision sensor).

How much does it cost to fix B004B?

It depends on what needs to be fixed. Clear crash data and reset SRS module after repair repairs are cheaper (~$200), while Replace faulty airbag deployment control module or sensor repairs are on the higher end (~$1500).

Does code B004B apply to Chevrolet vehicles?

Yes, B004B is a generic code that applies to all OBD-II compliant vehicles, including Ford, Toyota, Honda, Chevrolet, Nissan, Dodge, BMW, and more.

User Comments (0)

Share your experience or ask a question about this code.

Be the first to share your experience with B004B!