Airbag Light On: Causes, Dangers & Solutions
Why is the airbag light on?
The airbag light stays on continuously when the control unit detects a fault in the restraint system. This means: The airbag system is deactivated and would not deploy in an accident. The most common causes are defective connectors, a worn spiral cable, a problem with the seat occupancy mat, or a faulty control unit.
The airbag warning light (also called SRS light) is one of the most important warning lights in the vehicle. It is normal for it to light up briefly when the engine starts – then it must go out. If it stays on continuously, there is a specific fault that affects the safety of all occupants.
The most common causes at a glance
The top causes for a continuously illuminated airbag warning light are defective connectors, a worn spiral cable, problems with the seat occupancy mat, a faulty seat belt buckle, crash data in the control unit, and battery problems. In most cases, the control unit itself is not defective.
| Cause | Description | Frequency |
|---|---|---|
| Spiral cable defective | Conductor track in steering wheel slip ring broken | Very common |
| Seat occupancy mat defective | Sensor under passenger seat worn | Very common |
| Connector/cable break | Corroded or loose connections | Common |
| Seat belt buckle contact | Defective sensor in seat belt buckle | Common |
| Crash sensor defective | Impact sensor provides no signal | Moderate |
| Crash data in control unit | Data stored after accident | Moderate |
| Control unit internally defective | Hardware fault on circuit board | Moderate |
| Battery problems | Voltage too low or voltage spikes | Low |
| Blown fuse | Short circuit in airbag circuit | Rare |
Top 3 most common sources of error
The spiral cable, the seat occupancy mat, and defective connectors together account for the majority of all airbag warning light cases. These components are subject to natural wear – the spiral cable from constant steering, the seat occupancy mat from passenger weight, and connectors from vibrations and moisture.
What dangers exist?
When the airbag warning light is on, the entire SRS system is deactivated. In an accident, neither airbags nor seat belt tensioners will deploy – the driver and passenger are exposed to significantly increased risk of injury. Additionally, the TÜV inspection will fail.
| Danger | Impact | Urgency |
|---|---|---|
| Airbags do not deploy | No impact protection in frontal/side crash | Very high |
| Seat belt tensioners do not function | No optimal seat belt positioning in accident | High |
| TÜV deficiency | Major defect, no inspection sticker | High |
| Insurance risk | Possible benefit reduction if defect is known | Moderate |
Can I continue driving with the airbag light on?
The vehicle is drivable and there is no immediate breakdown risk. However, the vehicle no longer offers airbag protection in an accident. Driving to a workshop is possible, but longer trips without a functioning airbag system are not recommended.
- Drive to workshop:Yes – but schedule an appointment soon
- Longer distances:Not recommended without occupant protection
- Clear it yourself:Not possible and not permitted – only for qualified personnel
- Ignore it:Dangerous – protection is not guaranteed
How is the cause diagnosed?
Diagnosis is performed by reading the fault memory in the airbag control unit via the OBD-2 interface. The stored fault code shows exactly which component is causing the fault – whether spiral cable, seat occupancy mat, crash sensor, connector, or the control unit itself.
- Read fault memory:Connect diagnostic device to OBD-2 port
- Interpret fault code:Which component is named in the code?
- Check component:Inspect connectors, cables, and affected component
- Replace/repair defective part:Spiral cable, mat, sensor, or control unit
- Clear fault memory:Reset code after repair
- Function test:Warning light must go out after engine start
What solutions are available?
The solution depends on the cause: A defective spiral cable or seat occupancy mat is replaced, damaged connectors are repaired, and a faulty control unit is professionally serviced. In all cases, the fault memory must then be cleared – only then will the warning light go out.
| Cause | Solution | Professional service required |
|---|---|---|
| Spiral cable defective | Install new spiral cable | Yes (airbag removal required) |
| Seat occupancy mat defective | Install new mat | Yes (seat removal required) |
| Connector corroded | Clean or replace | Recommended |
| Seat belt buckle defective | Replace seat belt buckle | Yes |
| Crash sensor defective | Replace sensor | Yes |
| Crash data in control unit | Have data cleared | Yes (special tools required) |
| Control unit internally defective | Repair by professional service | Yes |
| Battery weak | Charge or replace battery | No |
Repair at Airbag24
You can find the exact costs for repairing your airbag control unit or the right replacement for spiral cables, seat occupancy mats, and crash sensors in our shop. At Airbag24, we help you with all problems related to the airbag warning light – with over 20 years of experience and 10,000+ satisfied customers.
Frequently asked questions about the airbag warning light
Here you will find answers to the most important questions about the illuminated airbag light.
Can I turn off the airbag light myself?
No. The warning light can only be turned off by fixing the cause and then clearing the fault memory with a diagnostic device. Independently interrupting the light (e.g., by removing the bulb) is not permitted and is dangerous – the defect remains.
Does the airbag light come on after a battery change?
Yes, that can happen. The voltage interruption can cause the control unit to store a fault. In many cases, the light goes out on its own after a few driving cycles. If it stays on, the fault memory should be read and cleared at a workshop.
What does it cost to repair when the airbag light is on?
The cost depends on the cause. You can find exact prices for replacement parts and repairs for your vehicle model in our shop. At Airbag24, you get suitable spiral cables, seat occupancy mats, crash sensors, and control unit repairs for all brands.
Is the airbag light relevant for TÜV inspection?
Yes. A continuously illuminated airbag warning light is classified as a major defect during the main inspection. The vehicle will not receive a new TÜV inspection sticker. The defect must be fixed before the next inspection.