Can you drive without a torsion bar?
Can you drive without a clock spring?
Technically, the vehicle is roadworthy with a defective clock spring – but the driver airbag is non-functional and would not deploy in an accident. Additionally, the horn and steering wheel buttons often fail. Driving without a functioning clock spring poses a significant safety risk and will result in the inspection authority (TÜV) refusing to issue the inspection sticker.
The clock spring (also called a slip ring, spiral cable, or clock spring) is a flat ribbon cable in the steering wheel that establishes the electrical connection between the rotating steering wheel and the stationary dashboard. It supplies power to the driver airbag, horn, and multifunction buttons. When defective, all these functions are affected – with direct implications for safety.
What happens with a defective clock spring?
When a clock spring is defective, the internal flat ribbon cable tears – the electrical connection to the driver airbag is interrupted. The SRS control unit detects the fault, stores an error code, and disables the driver airbag. The airbag warning light illuminates continuously.
| Function | Impact if Defective | Safety-Relevant? |
|---|---|---|
| Driver airbag | Will not deploy in accident | Yes – life-saving function fails |
| Horn | No longer functions | Yes – mandatory equipment per traffic regulations |
| Multifunction buttons | Steering wheel buttons non-functional | No – comfort feature |
| Shift paddles (if present) | May fail | No – comfort feature |
| Cruise control operation | May fail | No – comfort feature |
Important: Even if the horn still works, the clock spring may still be defective. The clock spring has multiple conductors – in the VW T4, for example, it has 5 pins with separate lines for the airbag and horn. Only the airbag line may be torn while the horn still has contact.
What risks exist when driving without a clock spring?
The greatest risk is the lack of airbag protection: in a frontal collision, the driver airbag is not available. Additionally, the missing horn can become dangerous in traffic. Insurance and inspection issues also arise.
| Risk | Description | Consequence |
|---|---|---|
| No airbag protection | Driver airbag does not deploy in accident | Increased risk of injury in frontal impact |
| No horn | Sound signal not possible | Violation of traffic regulations, traffic hazard |
| TÜV deficiency | Airbag light continuously on | No new inspection sticker issued |
| Insurance issues | Known defect in safety system | Possible reduction in benefits for personal injury claims |
| Unintended deployment | Intermittent contacts from partial break | Theoretically unlikely, but not excluded |
Is there a risk of unintended airbag deployment?
Unintended airbag deployment due to a defective clock spring is extremely unlikely in practice. The control unit detects the interruption and deactivates the ignition circuit. The airbag neither deploys accidentally nor functions in a real accident – both problematic, but the risk of unintended deployment is minimal.
TÜV and Operating License: What are the legal requirements?
A continuously illuminated airbag warning light is classified as a major deficiency during the main inspection – the sticker will be refused. However, the operating license does not automatically expire due to a defective clock spring alone, as no law mandates airbag equipment. A non-functioning horn is, however, a separate violation of traffic regulations.
- Inspection/TÜV: Airbag warning light continuously on = major deficiency, no sticker issued
- Operating license: Does not expire solely due to airbag defect (§19 traffic regulations)
- Horn: Mandatory equipment per traffic regulations – defective horn is a separate deficiency
- Modern inspection procedure: Control unit is read out, error code manipulation is detected
Repair or replace the clock spring?
A defective clock spring can either be replaced with a new part or repaired by a specialist shop. Replacement requires removal of the driver airbag – this falls under explosives law and may only be performed by qualified personnel. Self-repairs on the steering wheel are not permitted.
| Option | Description | Note |
|---|---|---|
| Install new part | Original clock spring from manufacturer | Expensive (often €200–500), specialist workshop only |
| Have clock spring repaired | Replace torn flat ribbon cable | More affordable, available with warranty from specialist shops |
| Used replacement part | Install used clock spring | Risk of unknown prior damage |
Why is self-repair prohibited?
To replace the clock spring, the driver airbag must be removed. Since the airbag contains a pyrotechnic gas generator, handling falls under explosives law. Work on pyrotechnic safety systems may only be performed by persons with appropriate qualifications. Improper handling can cause unintended airbag deployment.
How do I recognize a defective clock spring?
Typical signs include: airbag warning light illuminates continuously, horn does not work, steering wheel buttons do not respond, and cracking or grinding noises are heard when steering. Often the defect develops gradually – individual functions fail first before the airbag light comes on.
- Airbag warning light: Illuminates continuously after engine start
- Horn: No response when pressed
- Steering wheel buttons: Multifunction buttons, cruise control, or phone buttons do not respond
- Noises: Cracking, grinding, or scraping sounds when steering
- Error code: Diagnostics show error in driver airbag ignition circuit
Does Airbag24 repair clock springs?
No, Airbag24 does not offer clock spring repair. Our specialty is repairing airbag control units and selling simulators for seat occupancy mats. However, if your airbag warning light is on, the problem is not always the clock spring – often a defective airbag control unit is the cause.
- Airbag control unit repair: We repair defective airbag control units for all common makes and models
- Seat occupancy mat simulators: Suitable simulators for seat occupancy detection in our shop
- Consultation: Are you unsure whether the control unit or clock spring is defective? We'll help you with diagnostics
Frequently asked questions about driving without a clock spring
Here you'll find answers to the most important questions about clock springs and driving safety.
How long can you drive with a defective clock spring?
The vehicle is technically roadworthy, but the driver airbag is deactivated. The longer you drive with the defect, the longer you're on the road without airbag protection. Prompt repair is strongly recommended – especially if the horn has also failed, as it is mandatory equipment.
Can the clock spring break while driving?
Yes, it happens. The clock spring wears with every steering movement over the years. The flat ribbon cable often breaks suddenly – recognizable by the airbag light illuminating while driving and the horn or steering wheel buttons failing at the same time.
Will the airbag deploy in an accident anyway?
No. With an interrupted clock spring, the control unit can no longer electrically ignite the gas generator in the airbag module. The driver airbag will definitely not deploy in a frontal collision. The passenger and side airbags are not affected by the clock spring and continue to function.
What does clock spring repair cost?
Costs depend on the vehicle model. New parts cost between €60 and €500 depending on the manufacturer, plus installation. Professional repair of the flat ribbon cable by a specialized shop is usually significantly cheaper. Ask your workshop about the options for your specific vehicle model.