GarthWilson

I purchased a demo model A3 1.8 TFSI Sedan mid 2016 (2015 model) from the local Audi dealership in Cape Town, South Africa. The vehicle has now done around 24,000 km.
The car is equipped with both Pre Sense front and Adaptive Cruise control.
I recently had 3 malfunctions of the Pre Sense system:

1. A sound "ping" with a red triangle warning on the display while cruising at around 120 kph on a motorway. The system did not apply the brakes and the warning disappeared in a second or so. The road ahead was completely clear with no traffic or other obstacles anywhere nearby.
2. The car brought to an emergency, complete stop while driving slowly into a parking garage. This also with the warning display and ping. No vehicle or object in front of the car. Fortunately no car behind either.
3. Car given a brake jolt while driving on suburban roads at around 60 kph with the same dashboard warning and ping sound.

The car spent 2 weeks with the local Audi dealership where they checked the system and replaced a relay and the pre sense control unit after the 2nd incident. At the time they could not identify any faults in the system. The 3rd incident happened 4 days ago and I am waiting for Audi's response on what course of action they will take.

I would be interested to know if any similar Pre Sense malfunctions have been experienced and what the causes have been if these are known.

I am nervous to drive the car as is, as a sudden stop in traffic will likely result in a rear end collusion. Switching the system off is a nuisance as it reverts to the on status next time the car is started, and according to Audi there is no way to switch it off permanently.

Thanks in advance for any responses

Flying Scotsman

That is unsettling and one reason I do not like these autonomous devices that are in their infancy. There was a person on another site that had the same issue of the brakes slamming on in the UK. That car was replaced with a new one as Audi could not resolve the issue after multiple attempts to fix it. I do not believe Audi when they say they can not switch it off permanently, they are just stating that for liability issues. They state the same for auto start/stop and there are modules that can be wired into the system to do this, and OBD dongles that also accomplish this and more. .
By the way how is the water supply system doing, any more doomsday dates?

onthesam

I'm dealing with a similar issue - my 2017 A3 e-tron (US) pre sense activates when I drive across certain open metal grate bridges with no actual obstructions in front of me during twilight hours. Applies full-on emergency breaking and tightens seat belt creating a very dangerous situation. I don't know the cause yet but given that mine occurs on very specific types of bridges, I'm hopeful we can find what's up.

Timmay

Damn, that sounds like it needs a serious calibration! Either that or I would want it completely disabled. I have driven different cars for many years without high tech grannies overriding me and I've been just fine. This would be alarming indeed.

onthesam

A follow-up on my earlier post about pre sense activating on open metal grate bridges on the 2017 A3 eTron:

I took the vehicle in to a local dealer to investigate the problem. They initially wanted to test drive with me to reproduce the problem but ultimately determined that attempting to reproduce on public roads was not a safe idea. They purportedly tested the system and reported no faults. They measured value blocks to the pre sense module and reported everything is performing to manufacturer's specification. They also inspected pre sense sensors and the windshield for damage and found none. In the end they told me that I'll just have to be careful when crossing bridges.

Any thoughts on next steps or how to escalate? Is AoA the best route? Selling dealer (I'm in IL, dealer in CA). The problem persists...

gamegenie

My thoughts onthesam is don't waste your time on AoA, they will probably refer you right back to the service center of the dealer. I trade that sucker in for non-equipped front sensor e-tron.

rorlando618

2018 A5 Sportback...same thing. It happened at least 10 times within the first 3K miles. I have a bad back and it really torqued my back for 3-weeks I could not move.

2intense

tjacoby

We've had good success in taping over the front sensors to disable presense functionality in BMW and Lexus cars - haven't tried it with Audi yet. We need it disabled for cars used in professional bicycle road races, and can't rely on volunteer drivers to always remember to disable the functionality with the cars being restarted many, many times during an event. might be worth trying if you need a more permanent disactivation option. For our events we do both the dash sensors and the sensors in the rear view mirror, although I'd think only the dash sensors would be required.

I've had my RS3 presense sensors realigned once under warranty, and do find the system overly cautious while parallel parking in traffic, so far so good out in the real traffic.

2intense

In our case it's the 1.8L A3 equipped with "Pre Sense Basic" which has no sensors, only tseatbelt tightening and automatic window rollup.