B0038

What it means

B0038 is the generic code for a fault in the deployment control circuit for the second row right side airbag. This is usually a side or curtain airbag on the rear right of the vehicle. The airbag control unit runs self-tests on the deployment loop (the squib circuit) and set this code because it saw a resistance or voltage outside the expected range. The cause could be an open circuit, a short to ground or voltage, or a fault in the airbag module itself. The exact fault type depends on the model.

Symptoms

• Airbag warning light on the dashboard, either lit constantly or flashing
• Airbag system self-test fails at ignition on
• Rear right airbag may not deploy in a collision
• Seat belt pretensioner or other side airbag faults stored alongside it
• Passenger airbag status or seat occupancy warnings in some models
• Fault returns after clearing, or comes and goes when the rear seat is moved or the car hits bumps

Possible causes

• Damaged, corroded or loose connector at the rear right seat, pillar or door area (often disturbed by seat removal or trim work)likely
• Chafed, pinched or broken wiring in the loop to the second row right airbag, for example at a door or pillar flexing point or under the seatlikely
• Faulty airbag module (squib) with out-of-range resistancepossible
• Poor connection at the airbag control unit connector or the yellow in-line connectors under the seatspossible
• Water ingress or corrosion in the rear cabin wiring after a leak or previous repairpossible
• Fault in the airbag control unit's deployment driver circuitrare
• Incorrect or non-approved parts fitted after accident repair, or an incomplete repairrare

How to diagnose

1. Scan the airbag control unit for all stored and history codes, and read the fault status and any freeze frame or counter data. Note whether the fault is current or intermittent, and which subtype is reported.
2. Check for related faults such as other rear airbag, pretensioner or seat occupancy codes, which could point to a shared wiring or connector problem.
3. Ask about recent history: accident repair, seat removal, trim work, water leaks or aftermarket fittings in the rear cabin.
4. Before touching any airbag connector, switch the ignition off, disconnect the battery and wait for the time stated in the manufacturer's procedure so the system can discharge.
5. Visually inspect the connectors and wiring at the rear right seat, pillar, headliner and door area for damage, corrosion, bent pins or poor locking.
6. Inspect the in-line connectors and the airbag control unit connector for security and contact condition.
7. Check the circuit continuity and resistance with the module unplugged, using only the manufacturer's approved method. Never apply a test meter or power directly to an airbag module or squib.
8. Check that the airbag module and wiring are the correct parts for the model and fitment, and check for any applicable software updates or service information.

How to fix

• Repair or replace damaged wiring using the manufacturer's approved method, and route and secure it correctly.
• Clean, repair or replace corroded or damaged connectors, and make sure they are fully seated and locked.
• Replace the faulty airbag module with the correct part, fitted to the manufacturer's procedure.
• Repair the source of any water ingress and dry or replace affected wiring and connectors.
• Replace the airbag control unit only if testing proves it is faulty, and follow the required programming procedure for the model.
• After repair, clear the code, re-run the system self-test and confirm the warning light stays off and no fault returns.

Can I keep driving?

Nearby codes

• B0033GenericSecond Row Left Frontal Stage 3 Deployment Control
• B0039GenericSecond Row Right Frontal Stage 1 Deployment Control