pre sense is just aweful
08-10-2019, 09:44 AM
#11
AudiWorld Super User
Presense once caused me to spill mustard all over my new Zegna when I was eating a hot dog on the way to work.
08-10-2019, 01:57 PM
#12
AudiWorld Junior Member
I was backing into a parking space; Presense detected the parkade's spinning ventilation fan and slammed on the brakes.
Spilled a half caf decaf with a twist of lemon all over my suede Ballys.
Spilled a half caf decaf with a twist of lemon all over my suede Ballys.
08-10-2019, 04:44 PM
#13
AudiWorld Super User
08-11-2019, 03:31 PM
#14
AudiWorld Uber User
Did it have a twist of lemon?
08-27-2019, 01:26 PM
#15
Two days ago I was on the highway, doing about 70mph. I had good distance between me and the car in front, maybe 6 car lengths.
Slight, quick glance over to the right as there was a semi going faster and approaching from the right rear.
Just as I was about to look back forward the vehicle ahead distance warning goes off and it felt like the system applied the brakes just as I saw the bright brake lights ahead, as my eyes were coming back forward, so I too applied the brake pedal.
It felt like both I and the system engaged the brakes at about the same time. IOW, the level of brake force was very hard, too hard given the distance between me and the car in front.
I know I'm ignorant for saying this, but I thought the auto-braking only engaged up to 30mph?
Initially the S4 veered slightly to the front left, then a harder rear right, moving me slightly over and nearer the approaching semi.
The overall feeling was as if I had not control over the car, due to unequal brake pressure distribution from front to rear and left to right.
It was very disconcerting, but I keep a light yet firm control over my steering wheel.
I've NEVER experienced that type of "loss of control" sensation in any of my cars since the early 2000s.
I've experienced that type of heavy braking in older cars with disc brakes but no ABS.
The calibration of this braking system seems off, and wrong. It could be the ABS and proportioning valve reacting slowly, badly.
This should not have happened at all in a 2018 sport sedan. It shouldn't happen in a modern economy sedan, let alone a "sport sedan" variant.
I'm due for my first service and I'll mention this to the service adviser, but I don't expect them to find anything, but I'll still mention it, just in case.
Slight, quick glance over to the right as there was a semi going faster and approaching from the right rear.
Just as I was about to look back forward the vehicle ahead distance warning goes off and it felt like the system applied the brakes just as I saw the bright brake lights ahead, as my eyes were coming back forward, so I too applied the brake pedal.
It felt like both I and the system engaged the brakes at about the same time. IOW, the level of brake force was very hard, too hard given the distance between me and the car in front.
I know I'm ignorant for saying this, but I thought the auto-braking only engaged up to 30mph?
Initially the S4 veered slightly to the front left, then a harder rear right, moving me slightly over and nearer the approaching semi.
The overall feeling was as if I had not control over the car, due to unequal brake pressure distribution from front to rear and left to right.
It was very disconcerting, but I keep a light yet firm control over my steering wheel.
I've NEVER experienced that type of "loss of control" sensation in any of my cars since the early 2000s.
I've experienced that type of heavy braking in older cars with disc brakes but no ABS.
The calibration of this braking system seems off, and wrong. It could be the ABS and proportioning valve reacting slowly, badly.
This should not have happened at all in a 2018 sport sedan. It shouldn't happen in a modern economy sedan, let alone a "sport sedan" variant.
I'm due for my first service and I'll mention this to the service adviser, but I don't expect them to find anything, but I'll still mention it, just in case.
Last edited by TT-S4; 08-27-2019 at 01:33 PM.
08-29-2019, 02:35 PM
#16
08-31-2019, 05:16 PM
#17
AudiWorld Super User
If you have ACC (and the long distance radars that come with that system), it will engage autonomous emergence braking at speeds up to 250km/h, which is 155mph.
If you just have Pre-Sense City, the camera can track at speeds up to 85km/h, or 53mph. If the vehicle it picks up is at a dead stop whilst you are doing 53mph, the car won't be able to stop in time. The maximum differential speed enabling the car to avoid a collision is 40km/h, or 25mph. It helps to grasp the concept that it is the speed differential that is being tracked by the system.
Broad explanations here, more info if you look at the model specific info on the same Audi site:
https://www.audi-mediacenter.com/en/...e-systems-7184
The system likely beat you, even if only by a fraction, as it typically will not engage if you already had your foot on the brake, and were braking adequately. Brake assist will cut in if the system still thinks you are going to crash - it uses the ESC system to individually control each brake to minimise a chance of skidding and to encourage / enable the driver to take some steering action to avoid a crash. Sounds a little like what you experienced. The most likely cause for weird steering/ brake behaviour would typically come from using a non-OEM wheel offset. Typically a lower offset as that moves the scrub radius in the wrong direction for an AWD car, but Audis are relatively tolerant.
If you just have Pre-Sense City, the camera can track at speeds up to 85km/h, or 53mph. If the vehicle it picks up is at a dead stop whilst you are doing 53mph, the car won't be able to stop in time. The maximum differential speed enabling the car to avoid a collision is 40km/h, or 25mph. It helps to grasp the concept that it is the speed differential that is being tracked by the system.
Broad explanations here, more info if you look at the model specific info on the same Audi site:
https://www.audi-mediacenter.com/en/...e-systems-7184
The system likely beat you, even if only by a fraction, as it typically will not engage if you already had your foot on the brake, and were braking adequately. Brake assist will cut in if the system still thinks you are going to crash - it uses the ESC system to individually control each brake to minimise a chance of skidding and to encourage / enable the driver to take some steering action to avoid a crash. Sounds a little like what you experienced. The most likely cause for weird steering/ brake behaviour would typically come from using a non-OEM wheel offset. Typically a lower offset as that moves the scrub radius in the wrong direction for an AWD car, but Audis are relatively tolerant.
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TT-S4 (09-19-2019)
09-02-2019, 08:53 AM
#18
Out of curiosity, was it a false alarm or did you attempt to pull out of your parking spot with one of your hands occupied holding your coffee and not paying enough attention while another car drove past your spot that you could have crashed into? Either way, I would say your hands belong on the steering wheel while making such a maneuver and the coffee goes in the cup holder, and pay attention to your surroundings. Just a bit of a rant on my end, because just this week I had to swerve around two separate cars pulling out of their parking spot w/o a care in the world while I was passing on the road behind them. The second one I only caught in the corner of my eye and I had to swerve into the adjacent lane to avoid being hit. This is the kind of people this system was made for. I'm aware there are reports of it being a bit too sensitive sometimes, and even having false positives, but I wish every car had this system so I don't have to swerve every time somebody isn't looking. Coincidentally, I witnessed the system working on a Q5 in a parking lot last week. This lady was starting to pull out w/o looking properly, while a car was just crossing behind her and the Q5 stopped on a dime. The lady visibly shaken up and I hope she learned her lesson and is thankful the system saved her from an accident.
+1
One of the best features of my 2018 S4 and 2019 Q8.
Drinking coffee (without a splash stick, I assume) while driving is a bit risky in traffic regardless of who or "what technology" jabbed the brakes.
I'm not a big fan of the government legislating our choices, but I do wish every car had the systems that come with the "driver assistance package" -- I prefer the safety net unless I am driving on a completely dedicated, deserted highway (which, these days, is virtually impossible to find).
I also am a huge fan of the automatic headlights.
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angrypengu (12-13-2019)
09-02-2019, 08:58 AM
#19
If you have ACC (and the long distance radars that come with that system), it will engage autonomous emergence braking at speeds up to 250km/h, which is 155mph.
If you just have Pre-Sense City, the camera can track at speeds up to 85km/h, or 53mph. If the vehicle it picks up is at a dead stop whilst you are doing 53mph, the car won't be able to stop in time. The maximum differential speed enabling the car to avoid a collision is 40km/h, or 25mph. It helps to grasp the concept that it is the speed differential that is being tracked by the system.
Broad explanations here, more info if you look at the model specific info on the same Audi site:
https://www.audi-mediacenter.com/en/...e-systems-7184
The system likely beat you, even if only by a fraction, as it typically will not engage if you already had your foot on the brake, and were braking adequately. Brake assist will cut in if the system still thinks you are going to crash - it uses the ESC system to individually control each brake to minimise a chance of skidding and to encourage / enable the driver to take some steering action to avoid a crash. Sounds a little like what you experienced. The most likely cause for weird steering/ brake behaviour would typically come from using a non-OEM wheel offset. Typically a lower offset as that moves the scrub radius in the wrong direction for an AWD car, but Audis are relatively tolerant.
If you just have Pre-Sense City, the camera can track at speeds up to 85km/h, or 53mph. If the vehicle it picks up is at a dead stop whilst you are doing 53mph, the car won't be able to stop in time. The maximum differential speed enabling the car to avoid a collision is 40km/h, or 25mph. It helps to grasp the concept that it is the speed differential that is being tracked by the system.
Broad explanations here, more info if you look at the model specific info on the same Audi site:
https://www.audi-mediacenter.com/en/...e-systems-7184
The system likely beat you, even if only by a fraction, as it typically will not engage if you already had your foot on the brake, and were braking adequately. Brake assist will cut in if the system still thinks you are going to crash - it uses the ESC system to individually control each brake to minimise a chance of skidding and to encourage / enable the driver to take some steering action to avoid a crash. Sounds a little like what you experienced. The most likely cause for weird steering/ brake behaviour would typically come from using a non-OEM wheel offset. Typically a lower offset as that moves the scrub radius in the wrong direction for an AWD car, but Audis are relatively tolerant.
09-09-2019, 04:54 AM
#20
AudiWorld Super User
The Q8, and the C8 A6/A7 and D5 A8 all have the additional zFAS layer that sits above the sensor layer, and draws a live 360° virtual environment around the car. It is effectively a form of AI, is autonomous Level Three capable, and is not present on the B9 models, including the new facelift despite that moving to the latest version of MMI (MIB3).