Interesting info on B8 engine cutoff from car accident
 

As I posted here before, on 1/10 I was in a rear-end car accident that essentially seemed to have disabled my B8. At first I thought it was because I was unable to disengage the ebrake and I kept getting ebrake malfunction on the driver display. It's been at the Audi dealer for a week now and for a few days they couldn't figure out how to start the car!! Luckily they did and I wanted to share this info with other B8 owners for reference.

According to the Audi dealer service tech, there's a supplemental system that's linked to the car's SRS (airbag) system that is triggered when the car detects a significant impact. In my case, the airbags didn't deploy but the impact was enough to trigger this supplemental system. This system he said is essentially a pyrotechnic/firecracker type device that explodes and cuts the hard line that provides power to the engine. The battery still powers accessories, nav, lighting, etc but things like the ebrake (now it makes sense), the engine, brakes, steering are cutoff from power!

So they eventually discovered this (not fully familiar with B8 yet) and reset this system. After doing this, the car started right up, the ebrake issue cleared up and they were able to drive the car to the body shop with no issues!!

SO, if you are ever unfortunate enough to be in an accident and your B8 won't start, you at least have a clue as to why!!

I hope to get it back in a week or two, but at least I know the car is working fine and it's just body work.<ul><li><a href="https://forums.audiworld.com/a4b8/msgs/24989.phtml">https://forums.audiworld.com/a4b8/msgs/24989.phtml</a</li></ul>

Wow... that's crazy. Glad it's working out for you though!

Wow, thanks for the info but...
 

you would think Audi service dept would have received professional training on the B8's the encompasses all aspects of the vehicle and not have to fiddle around like some amateur 2nd hand repair shop...very surprised and hope not to be this disappoint should I ever have a serious issue on my B8 and require dealer repair. Kind of scary if you ask me and makes you wonder what else they don't know...

What if you want to pull off the road after an accident to avoid causing a pile-up on a foggy day?
 

Does it have to be reset by VAG COM or is there a switch somewhere?

Re: What if you want to pull off the road after an accident to avoid causing a pile-up on a foggy da
 

The way they explained it to me, as I described, it's not an electronic disabler but an explosive/fuse type device that actually cuts the cable(s) to the engine. So the only way to fix it is with some physical work, probably replacing that fuse and reconnecting the cables.

It didn't sound like something that could be done after an accident.

I had the same problem that I wanted to pull off the road, since my accident happened in an extremely busy state highway!! Guess just wait for a flatbed!

Re: Wow, thanks for the info but...
 

Agree, I was disappointed and worried when they told me they couldn't figure out how to start the car!! An Audi dealership and let alone the place I bought the exact car from!

I think the issue is they've probably received the training for maintenance and repair but because it's still so new, maybe not on this level of restoring after an accident.

Hmm, I wonder if this feature is actually more risky (in the situations mentioned)

Unpossible....
 

...if it is a "essentially a pyrotechnic/firecracker type device that explodes and cuts the hard line that provides power to the engine" then it can't be "reset."

Ask him to show you that in the service manual.

Methinks that the techs are clueless and started resetting stuff until the car started working again. BMWBig6 raises a good question - the engineers would not have designed it this way....

Makes no sense....
 

Why in the world would a light accident as you seemed to have had require an "explosive device" that disables the car in this fashion? This would seem to be more dangerous not being able to drive it off the road than preventing you from driving it away. I don't get it.

And an explosive device? What if there's a fuel spill as a result of the accident? Wouldn't there be a danger of igniting the spilled fuel from this device? Makes no sense to me.

Methinks I'm going to dig deeper into this with AOA.

I agree... would love to hear what you find out.