[chaicc]

We were in our new X7 2024. Driving at around 20-30mph in left lane with AD( assisted driving) on and my hand on stearing wheel. My foot hovering over brake pedal ( as i have not trusted AD or ADP fully yet).

Car in front of me comes to a sudden stop and usually my car would slow down and even stop to maintain the distance when AD is on.
This time to my surprise, it didn't. It gave frontal crash warning by showing a red car icon on HUD and also a message (i don't remember the exact statement ) on the lines of "take control of the brake and apply it"

By the time my brain was figuring out, seeing the crash warning icon, reading the message, listening to audible alert sound, my car applied brake automatically. I couldn't figure out if it was the car applying the brake automatically or I put my foot down on the brake( remember i keep it hovering all the time). But somehow the crash was averted.

Now first thing i wanted to do was come here and share with you all that please take precautions with AD and most importantly ADP. I previously also had a minor issue with ADP when it sped up instead of slowing down upon taking an exit which kind of freaked me out but i ignored. But now i am being extra careful with AD and ADP.

by the way, is there an automatic braking intervention thing or was it me braking in panic(for good)?

Anyway, stay safe. Thanks

[MystroX5]

I had a similar story with the vehicle auto steering and braking. I am a believer.

https://g05.bimmerpost.com/forums/sh....php?t=1580609

High Speed Collision Avoidance works.
I am in the middle of a 2200 mile family roadtrip with my family in my new X5 50i M-Sport. 200 miles on the odometer when we left from PA to Florida. Construction out side Orlando is a mess with multiple lane shifts and make shift construction zones. Traffic flow on 3 lanes was moving 75-80mph 3 accross and tight. A couple cars ahead couldn't make the 3 lane shift and the turns at that speed was too much for their skill level. So some slammed on their brakes causing multiple cars slamming into their sides and it was like a NASCAR wreck. My X5 was on ACC and as soon as I saw smoke and car parts flying into the air 8 cars up, my Collision Avoidance was already taking hold of the vehicle with a red beeping alarm and the sound of anti lock braking on full strength. Seatbelts tightened up and the X5 was slowing faster than the Toyoya Sequioa that his auto brake activated but ran into the car ahead. The X5 swerved into the left media allowing the Lexus RX350 behind me enough room to tap the Toyota Sequioa I was following. We managed to pass the carnage of cars on the left.
The take away is the M Brakes with advanced safety made our $100k X5 seem like a bargain. My wife was amazed. It out performed the other vehicles safety features around us by such a margin it was shocking. Obviously the driver is the biggest safety feature but in a urban area when forced to drive around inferior skill levels, I will take all the added safty edge I can buy.

[PinkNinja400Guy]

I had Active Side Collision Prevention activate for the first time a week ago.

I was driving in the left lane of a highway with DAPP active; all of a sudden my car shifted over to the very leftmost edge of the lane. And the instrument cluster had a small "Active Side Collision Prevention" message in it.

I had been slowly passing a Subaru, it was in my right blindspot at the time. I guess the X7 sensed the Subaru was about to hit me in the side, so it moved itself over to the left edge of the lane? Looking at the drive recorder footage, the Subaru couldn't have moved more than a few inches towards my X7, it was still well within its lane when my car moved over. But it's hard to tell from the footage due to the camera angle and field of view.

That was the first and only time I've ever seen that happen; I didn't even know the X7 had that feature. Modern tech is pretty neat.

[PinkNinja400Guy]

Originally Posted by MystroX5

... as soon as I saw smoke and car parts flying into the air 8 cars up, my Collision Avoidance was already taking hold of the vehicle with a red beeping alarm and the sound of anti lock braking on full strength. Seatbelts tightened up and the X5 was slowing faster than the Toyoya Sequioa that his auto brake activated but ran into the car ahead.

Every car has automatic front braking as a feature these days, but they're not all the same. Newer and higher end cars use better radars which work better at high speeds.

AAA did some research on this with a 2022 Chevy, Ford, Honda, and Toyota. They were almost always able to prevent a crash (stop before hitting) at 30mph, and in the other cases they significantly slowed down so the crash as at low speed. But when you go up to 40mph, they usually didn't manage to avoid the collision entirely, and the collisions were at higher speeds (the automatic system didn't slow down the car as much before the crash).

https://newsroom.aaa.com/2022/09/bra...-need-it-most/

It's due to some technical thing about radar being bad at detecting stationary objects as you're driving at higher speeds. While I don't know for sure, I would expect that the 2019+ X7 with its more expensive sensing package & processing units would perform better than those 2022 economy cars, and the new 2023+ X7 with even newer tech is probably even better.

Originally Posted by MystroX5

The take away is the M Brakes with advanced safety made our $100k X5 seem like a bargain. My wife was amazed. It out performed the other vehicles safety features around us by such a margin it was shocking.

The M Brakes didn't do anything to help you. Braking capability is based on the traction provided by your tires. Tires are the limiting factor; even the tiny brakes on a base X7 40i are way stronger than what your tires can handle.

If you live in the south, use summer tires, not all season. If you live further north, have a set of summer and winter tires. Even very high quality all season tires provide much less traction than summer tires (in summer, and winter tires in winter). And obviously get good quality tires, if you buy the low end crap you're making your car more dangerous.

[streborx]

Originally Posted by chaicc

We were in our new X7 2024. Driving at around 20-30mph in left lane with AD( assisted driving) on and my hand on stearing wheel. My foot hovering over brake pedal ( as i have not trusted AD or ADP fully

Was your left foot hovering over the brake while your right foot was depressing the gas, or does AD regulate both speed and braking for traffic conditions so neither foot was doing anything but hovering (not in pedal contact)? While many drivers use both feet to gas and brake simultaneously, AD systems are designed to do one or the other, and should automatically cut off gas pedal input and apply braking when collision avoidance kicks in. But pedal inputs should override AD - there are instances when gassing it to get out of the way can avoid collision. So it's not clear to me how a vehicle can respond to two competing commanders. What does the car do when AD says brake and the drivers says go?

My only experience with AD was one incident with lane keeping assist which tried to steer me into a group of cyclists that I had swerved left to provide clearance. I'm not sold on any of this ADAS technology and prefer controlling vehicles on my own.

[chaicc]

Originally Posted by streborx

Was your left foot hovering over the brake while your right foot was depressing the gas, or does AD regulate both speed and braking for traffic conditions so neither foot was doing anything but hovering (not in pedal contact)? While many drivers use both feet to gas and brake simultaneously, AD systems are designed to do one or the other, and should automatically cut off gas pedal input and apply braking when collision avoidance kicks in. But pedal inputs should override AD - there are instances when gassing it to get out of the way can avoid collision. So it's not clear to me how a vehicle can respond to two competing commanders. What does the car do when AD says brake and the drivers says go?

My only experience with AD was one incident with lane keeping assist which tried to steer me into a group of cyclists that I had swerved left to provide clearance. I'm not sold on any of this ADAS technology and prefer controlling vehicles on my own.

AD does both breaking and acceleration. So i keep my foot hovering over brake only.

[Qsilver7]

If you saw the red car…then also heard beeping and the red car flashing…and you were going between a certain speed…then braking mitigation was applied…especially if it was sudden and severe. This is the ACUTE WARNING w/BRAKING.

There is info in the owners manual embedded in iDrive that will give you details on how/when braking mitigation kicks in. And if you have newer BMWs like iDrive 5/6/7/8…there’s probably embedded videos in iDrive that also gives details how the auto braking systems work and when.

The images below are from my older iDrive/NBT ID4…so if I have this info…I’m sure that your newer BMWs have this info and possibly more.

[chaicc]

Originally Posted by Qsilver7

If you saw the red car…then also heard beeping and the red car flashing…and you were going between a certain speed…then braking mitigation was applied…especially if it was sudden and severe. This is the ACUTE WARNING w/BRAKING.

There is info in the owners manual embedded in iDrive that will give you details on how/when braking mitigation kicks in. And if you have newer BMWs like iDrive 5/6/7/8…there’s probably embedded videos in iDrive that also gives details how the auto braking systems work and when.

The images below are from my older iDrive/NBT ID4…so if I have this info…I’m sure that your newer BMWs have this info and possibly more.

Thankyou this is very helpful

[entendu]

Originally Posted by PinkNinja400Guy

The M Brakes didn't do anything to help you. Braking capability is based on the traction provided by your tires. Tires are the limiting factor; even the tiny brakes on a base X7 40i are way stronger than what your tires can handle.

Although tire grip is the ultimate limiting factor (can’t have more stopping power than tires have grip), it is certainly possible to have brakes and ABS systems that result in braking performance below the theoretical tire limit.

https://youtu.be/HbR64hqx4Yk?feature=shared at 16:15, the model x plaid has famously undersized brakes and it shows. This tracks with my personal experience with the plaid. Weight is also a factor but it’s only a couple adults heavier than the X5M in the video (+340lbs) and about the same as an X7.

[chaicc]

I guess my biggest concern is that AD gave up all of a sudden. it asked me to take over where it was supposed to handle the situation. All it needed to do was slow down or brake.

It's comforting to know that brake intervention and other collision avoidance features are present. But why AD, why did you fail me.

With this incident, i have lost confidence on AD & ADP but gained enormous confidence on automatic brake intervention and frontal collision avoidance.

[MystroX5]

Ultimately I am the same way and never fully trust any automated systems fully. I pray they do work when my reflexes are not fast enough or outside the bubble of safety around my BMW gets compromised.

[chaicc]

Originally Posted by MystroX5

Ultimately I am the same way and never fully trust any automated systems fully. I pray they do work when my reflexes are not fast enough or outside the bubble of safety around my BMW gets compromised.

Agreed

[Qsilver7]

Have you watched the embedded video in iDrive on Assisted Driving Plus? It shouldn’t be hard to find…just open the owners manual in iDrive and go to USER HELP (that’s where all the videos are)…then scroll down to & select Assisted Driving Plus to start the video. It may give you some better ideas of how it’s supposed to work.

There’s also other videos that may be of interest like:

• Active protection
• Evasion assist
• Steering & traffic jam assist
• Person warning w/cit5y braking