# Will Airbag Deploy If Car is Off? **URL:** \ **Category:** General Discussion\ **Created:** [June 1, 2012, 2:14am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777 "2012-06-01T02:14:15Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![flvolleyballboy](https://avatars.discourse-cdn.com/v4/letter/f/ccd318/32.png) [@flvolleyballboy](https://community.cartalk.com/u/flvolleyballboy)\ **Post date:** [June 1, 2012, 2:14am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/1 "2012-06-01T02:14:15Z")
Will an airbag still deploy if the car was on, but while driving you turn the key to the off position, specifically a 2006 Lexus Hybrid RX 400H? ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [June 1, 2012, 2:24am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/2 "2012-06-01T02:24:09Z")
??? Why would you turn the ignition off while driving? Since that would deprive you of power steering and power brake assist, it is…not a wise thing to do. ??? ---
**Author:** ![bscar2](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bscar2/32/2468_2.png) [@bscar2](https://community.cartalk.com/u/bscar2)\ **Post date:** [June 1, 2012, 2:26am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/3 "2012-06-01T02:26:09Z")
hypermiling? ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [June 1, 2012, 2:32am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/4 "2012-06-01T02:32:05Z")
I’m guessing there’s MUCH more to this question… ---
**Author:** ![oblivion](https://avatars.discourse-cdn.com/v4/letter/o/3ab097/32.png) [@oblivion](https://community.cartalk.com/u/oblivion)\ **Post date:** [June 1, 2012, 2:33am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/5 "2012-06-01T02:33:43Z")
Yes, it will. ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [June 1, 2012, 2:38am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/6 "2012-06-01T02:38:13Z")
It is a good question and one I would like to know the answer to. I may just search the world wide wiver of infowmation! I had a friend who was rear ended while waiting in line at a parking garage, the airbags did not deploy with the rear impact but did when hitting the vehicle in front of them. Are airbags different now than their 04 Saturn I believe it was? Say you stop turn the engine off and in park, talking on the cell, if a similar action happened as described would the airbags go off? ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [June 1, 2012, 2:45am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/7 "2012-06-01T02:45:01Z")
**“I had a friend who was rear ended while waiting in line at a parking garage, the airbags did not deploy with the rear impact but did when hitting the vehicle in front of them.”** Your friend’s airbags worked exactly as they were intended to. Rear impacts throw passengers backwards (you know–the “whiplash” effect), and as a result, airbags deploying from the dashboard would be of no help to them. And, when airbags deploy needlessly, there is a lot of expense involved in replacing them after that unnecessary deployment. Head restraints are mandated in order to protect against rear impacts, since airbags are useless in that type of situation. Think about it… Then, in a frontal impact, the airbags did deploy. Nothing strange here, except for your understanding of airbag function… **;-))** ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [June 1, 2012, 3:03am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/8 "2012-06-01T03:03:30Z")
But will they deploy if the engine is off? I get the not deploying in a rear impact concept but my friends head busted the windshield before the airbags went off, due to the let’s call it rebound effect, hit the headrest then bounced forward, hit the windshield, then car in front that deployed the airbags. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [June 1, 2012, 3:11am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/9 "2012-06-01T03:11:14Z")
Barkydog– I also do not know whether airbags will deploy if the engine is turned off. However, I do know that I have no plans to shut my engine off while driving, and I’m confident that you are also too intelligent to do that. Now, if we can just get the OP to explain the background for his question… ---
**Author:** ![oldbodyman](https://avatars.discourse-cdn.com/v4/letter/o/bbce88/32.png) [@oldbodyman](https://community.cartalk.com/u/oldbodyman)\ **Post date:** [June 1, 2012, 3:18am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/10 "2012-06-01T03:18:43Z")
If the key is off the air bags will not go off. For the air bags to go off computer needs to have power. The computer needs input from the sensors in order to deploy the air bags. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [June 1, 2012, 3:40am UTC](https://community.cartalk.com/t/will-airbag-deploy-if-car-is-off/72777/11 "2012-06-01T03:40:39Z")
The airbags won’t deploy on a parked car but in this case they are still active for a short period of time due to the capacitor or “backup power source”. Should power be cut to the control module during a collision the control module relys on the backup power source. Precautions are to wait 90 seconds after power disconnect before servicing the airbag system. From the service manual; "(5) Backup power source The backup power source consists of a power supply capacitor and a DC-DC converter. If the power system does not function during a collision, the power supply capacitor discharges and supplies electric power to the system. The DC-DC converter operates as a boosting transformer when the battery voltage falls below a predetermined level."