B1002–B1003 Igniter, Front Passenger Frontal Airbag - Stage 1 (N131)
The ECU has logged a fault on B1002. The definition below is the exact wording the standard uses for this code.
Can you drive it? This is a restraint-system fault. The airbag or belt tensioner may not deploy in a crash, and in some failure modes may deploy when it shouldn't. Have it looked at before carrying passengers.
Which code is which
Same fault, different cylinder or bank — diagnosed the same way. Several set together usually means one shared cause.
| Code | Definition | Severity |
|---|---|---|
B1002 | Igniter, Front Passenger Frontal Airbag - Stage 1 (N131) | Safety system |
B1003 | Igniter, Front Passenger Frontal Airbag - Stage 2 (N132) | Safety system |
The definition
B1002: Igniter, Front Passenger Frontal Airbag - Stage 1 (N131).
B1002 is a manufacturer-specific body code (an interior or comfort system). Its meaning is set by the carmaker rather than by the SAE standard, so a generic OBD-II reader will often show it as an unknown code or misread it.
What to check first
Cheapest and fastest checks first:
- Read the freeze-frame data stored with the fault - engine speed, load and temperature at the moment it logged tell you whether this happens cold, hot or under load.
- Check the connector at the part for corrosion, and that it is fully seated.
- Clear the code and see whether it returns, and under what conditions.
What actually causes this on a VAG
This is the firing circuit for the first stage of the front passenger's frontal airbag (N131 in VAG's own naming). The airbag control module checks that circuit continuously, and this code means it has found it open, short circuited or outside its expected resistance range. While the fault is stored the airbag warning light stays on, the passenger airbag may not deploy in a crash, and depending on the fault other restraints on that side can be disabled too - so the car is genuinely not in a safe state. On vehicles first used on or after 1 January 2004, an SRS warning light indicating a fault is also an MOT failure in its own right.
Most likely causes, in order
- Airbag connector not fully latched, or corroded. By far the most common trigger, and the first thing to look for - particularly if this appeared soon after work on the glovebox, dashboard, windscreen, heater or the passenger footwell, or after any water getting in down there. These plugs have a coloured locking clip that must be pushed fully home; half-seated is enough to set this code, and seating it properly is the whole repair.
- Damaged wiring under the dash or in the passenger footwell. The airbag loom can be trapped, pinched or pierced by trim screws, or disturbed when aftermarket accessories are fitted under the dashboard. Look for the loom being pulled tight, chafed against a bracket, or routed somewhere it clearly was not from the factory - dashcam and phone-charger installs are a regular culprit.
- The airbag unit or the airbag control module itself. Both are possible, but they are the last things to suspect rather than the first. A control module that has recorded a deployment, or one that has been sitting in a wet footwell, is a different and more serious situation than a loose plug, and it is not something to work around.
Worth knowing: Do not test an airbag circuit with a multimeter or a test lamp. Putting current through an igniter can fire it in your hands - that is the one genuinely dangerous mistake with this code. Looking for a plug that has not clicked home is fine; anything beyond that needs the system properly de-powered first (battery disconnected and left for the manufacturer's specified waiting time) and read with equipment made for airbag systems, which can identify the exact circuit instead of guessing. Ignore the resistor plugs and emulators sold to make the light go out: they satisfy the module's circuit check without restoring anything, so the light goes off and the airbag still does not fire. If the car has been in any kind of impact, assume the module and belt tensioners need checking too, and never let anyone simply clear the code to hide the light.
Reading the code is the easy part
A code names the circuit that complained. What tells you why is watching the sensor behind it while the engine runs — and that is where a code reader stops and a diagnostic tool starts.
VAGPULSE reads every module in a VW, Audi, Skoda or SEAT — not just the engine — shows the live measuring blocks behind this fault, gives you the freeze-frame conditions it was logged under, and clears it once you have fixed it. It also does what a generic OBD reader cannot on a VAG: service resets, coding, adaptations, and Stage 1–3 flashing with your original file saved first.
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Prefer to work on your phone? The VAGPULSE Android app is a free download and its demo mode runs against a sample car with no hardware at all, so you can see exactly what it reads before spending anything. Reading your car with it needs the VAGPULSE cable, which comes with the licence.
Common questions
What does B1002 mean?
B1002 means Igniter, Front Passenger Frontal Airbag - Stage 1 (N131). It is logged when the ECU sees this circuit outside its expected operating window.
Can I drive with B1002?
This is a restraint-system fault. The airbag or belt tensioner may not deploy in a crash, and in some failure modes may deploy when it shouldn't. Have it looked at before carrying passengers.