What Causes Airbags Not to Deploy?
2 Answers
Airbags not deploying does not necessarily indicate damage. It could also be because the conditions for airbag deployment were not met. Minor collisions will not trigger airbag deployment. Airbags are a passive safety system device. When a car collision occurs, the pressure sensors in the airbag system and the acceleration sensors in the ECU assess the collision. If the conditions for airbag deployment are met, both will receive signals simultaneously, causing the airbag to inflate instantly and protect the driver's head and chest, thereby ensuring personal safety. Necessary conditions for airbag deployment: 1. Vehicle speed: Generally above 50 km/h, but the key factor is the acceleration during the collision. In national certification tests, the instantaneous acceleration during collision is approximately -40g. 2. Frontal collision: The impact angle must be within approximately 60° of the front. 3. Collision object: Rigid walls or obstacles; airbags will not deploy when a car collides with soft objects at 80 km/h.
Last time I had a similar issue with car repair, a vehicle was badly damaged but the airbags just didn't deploy. Later inspection found that the frontal impact sensors were covered in mud and engine oil, affecting signal transmission and preventing impact detection. There could also be control system issues - aging airbag modules or software failures might cause failure to trigger. Electrical problems are common too - blown fuses or short circuits can interrupt signals. Additionally, if airbags exceed their 10-year service life, the internal propellant may degrade or the airbag cushion may rupture, requiring replacement. We recommend owners get professional diagnostics annually, especially after collisions - don't delay, go immediately to authorized 4S shops or repair centers for comprehensive inspection to prevent future accidents. Keeping sensors clean is also important - just do simple cleaning of the bumper area during regular car washes.
