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2018 Volvo S90 T4 Inscription full option
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Dear all,

since recently I owe a Volvo S90 (T4 Inscription, 2018), and I wondered about the following.
Suppose you are to hit the car in front of you; will your car stop by itself ? Is this really the case ? Or should some (extra) option be activated ?

Thanks !
 

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With City Safety it will try as long as you're not already braking. At higher speeds it is not within it's capability to stop, but it will try to slow down. There is a constant challenge between being so invasive that folks will hate it and giving you enough rope to hang yourself. Again, if you are braking, it won't brake harder.

City Safety info from Volvo
 

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Or should some (extra) option be activated ?
But if you've been paying attention, not diddling, and aware of your surroundings, maintaining a safe distance from the car in front of you, no option should need be activated. You should be able to apply your brakes and steer to avoid collision.

If you depend on your car to stop suddenly, you may find the driver behind you plowing into your rear.
 

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With City Safety it will try as long as you're not already braking. At higher speeds it is not within it's capability to stop, but it will try to slow down. There is a constant challenge between being so invasive that folks will hate it and giving you enough rope to hang yourself. Again, if you are braking, it won't brake harder.

City Safety info from Volvo
With City Safety it will try as long as you're not already braking. At higher speeds it is not within it's capability to stop, but it will try to slow down. There is a constant challenge between being so invasive that folks will hate it and giving you enough rope to hang yourself. Again, if you are braking, it won't brake harder.

City Safety info from Volvo
Based on the video I've linked to, I believe that current versions of City Safety WILL apply the brakes even if the driver is already braking if the driver's effort isn't sufficient and a collision is imminent. See the attached short video at 1:33.
 

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Based on the video I've linked to, I believe that current versions of City Safety WILL apply the brakes even if the driver is already braking if the driver's effort isn't sufficient and a collision is imminent. See the attached short video at 1:33.
Thanks for the update (though no video linked?)... I know improvements are always being worked on and frankly Volvo doesn't do the best job letting us know about all of them!
 

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I have an XC70 with the City Safety Collision Avoidance thingy and a couple weeks ago, on my way to work, there must have been frost on the windshield because when the sunlight hit the camera, my car must have thought there was a car in front of me and SLAMMED the brakes and brought me to an ABRUPT and scary stop...i was going maybe 25 or 30 mph...that was annoying...
 

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2020 S90 T6 Momentum, 2019 XC60 T5 Momentum (wife's)
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My Collision Avoidance activated when I was stopped at a red light. Some speed demon was speeding up to me to make a right turn, but he didn't turn until the last minute and the car thought I was going to be rear-ended. The seatbelts cinched up real fast and the system started flashing and beeping. Scared the crap out of me. If I had to go to the restroom, it would have been all in my pants... lol
 

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My Collision Avoidance activated when I was stopped at a red light. Some speed demon was speeding up to me to make a right turn, but he didn't turn until the last minute and the car thought I was going to be rear-ended. The seatbelts cinched up real fast and the system started flashing and beeping. Scared the crap out of me. If I had to go to the restroom, it would have been all in my pants... lol
I was just re-reading the owners manual and saw that feature, wondered what it would be like. In your opinion, does it seem like it is a real/useful feature that would help protect you?
 

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2020 S90 T6 Momentum, 2019 XC60 T5 Momentum (wife's)
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I was just re-reading the owners manual and saw that feature, wondered what it would be like. In your opinion, does it seem like it is a real/useful feature that would help protect you?
Yes, I think if I were re-ended, it would have definitely helped with whiplash/injuries. It pulls you in so tight, it forces your head against the headrest. But, it did scare the crap out of me...
 

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I was just re-reading the owners manual and saw that feature, wondered what it would be like. In your opinion, does it seem like it is a real/useful feature that would help protect you?
Absolutely! The Cito pre-tensioners pull you under the seat to help reduce whiplash injuries in the brakes are applied 100%. If you were hit from behind this lessens the chance of you being pushed forward like into an intersection and then being involved in a secondary impact. Applying maximum braking force is very important in the seatbelts also prepare you for that secondary collision if airbags are deployed.
 

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I was just re-reading the owners manual and saw that feature, wondered what it would be like. In your opinion, does it seem like it is a real/useful feature that would help protect you?
Emergency brake assist has been a part of our safety features for over 15 years. It absolutely is a key part of collision avoidance. As your closing in on a car breaking the vehicle calculates your closing distance and compares it to the breaking force you are applying. It does the mass to determine if that amount of break force is adequate avoid a collision. If it is not the car automatically applies additional braking force, and if it applies maximum brake application and tightens the electronic pre-tensioners if there is a high risk of a collision.

Just this week I had a deer run out and I applied the brakes in a panic but it would not have been enough. The cars analytical program also looks at the rate you take your foot off the Excelerator in the speed at which the brake is applied. The car assumes at a steady speed you rapidly release the gas pedal and stab the brake pedal you’re entering a panicked break situation and it will apply the electric free tensioner and full braking force. After a couple of seconds the system determines The cushion scenario and if need be reduces the amount of brake pressure.

This is something you can actually initiate on your own in a safe environment like an empty parking lot to become more familiar with what it’s like. If you drive along at 40 mph with your foot on the gas at a steady speed and then move your foot as quickly as possible from the gas to the brake pedal and apply about 25-50% brake pedal force by stabbing the brakes abruptly The electric pre-tensioners will activate in the car will apply 100% braking force. When the seatbelts tighten remove your foot from the brake pedal completely. You will see the car continues to break at maximum deceleration. After maybe two or three seconds is the car detects no pending collision in your foot off the break pedal it releases the brakes completely and the seatbelts loosen. It’s actually a little bit fun to see how it works and it’s probably useful in familiarizing yourself a little bit about what it feels like when the system activates.
 

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...
Just this week I had a deer run out and I applied the brakes in a panic but it would not have been enough. The cars analytical program also looks at the rate you take your foot off the Excelerator in the speed at which the brake is applied. The car assumes at a steady speed you rapidly release the gas pedal and stab the brake pedal you’re entering a panicked break situation and it will apply the electric free tensioner and full braking force. ...
I have had this engage on other cars, it is amazing how forceful today's cars can brake. My last car hit over 1 G with the 6 piston 15.4" fronts.

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This is something you can actually initiate on your own in a safe environment like an empty parking lot to become more familiar with what it’s like. If you drive along at 40 mph with your foot on the gas at a steady speed and then move your foot as quickly as possible from the gas to the brake pedal and apply about 25-50% brake pedal force by stabbing the brakes abruptly The electric pre-tensioners will activate in the car will apply 100% braking force. When the seatbelts tighten remove your foot from the brake pedal completely. You will see the car continues to break at maximum deceleration. After maybe two or three seconds is the car detects no pending collision in your foot off the break pedal it releases the brakes completely and the seatbelts loosen. It’s actually a little bit fun to see how it works and it’s probably useful in familiarizing yourself a little bit about what it feels like when the system activates.
I'd love to do the collision test, but obviously, that basically is dumb, but still the tech amazes me.
 

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Have you ever been waiting behind someone who doesn't know how to enter an expressway and they come to a complete stop, then see an opening and start to go...and then stop again while you're following them but looking back at on-coming traffic as you accelerate...into their rear-end? Your Volvo will save you. Guess how I know.
 

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Have you ever been waiting behind someone who doesn't know how to enter an expressway and they come to a complete stop, then see an opening and start to go...and then stop again while you're following them but looking back at on-coming traffic as you accelerate...into their rear-end? Your Volvo will save you. Guess how I know.
I got rear ended by that situation once. In a Dodge Rampage (VERY small 1980s FWD pickup based off the Omni), a Chevy Trailblazer did that. My head went backward and blew out the rear window (well the window went forward into my head but...) And there is a ramp near me that it can happen easily. I have learned to look hard to expect that now, literally driven into my head to think of those situations.
Good to know that Volvo's tech worked to save you and the guy in front, it can happen easily enough.
My Rampage (converted to Shelby Charger Turbo spec)

Packing tape at work holding the glass together afterwards, and tint held it on the inside.
Buckled the bed floor a bit, but was sold and repaired by another collector.
Tire Wheel Car Vehicle Automotive tire

I forgot about the [email protected] sticker, I need a new one! (Picksburghese) n'at. Like
"Yinz guyz like how safe doze new Volvo's are n'at?"
 

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Have you ever been waiting behind someone who doesn't know how to enter an expressway and they come to a complete stop, then see an opening and start to go...and then stop again while you're following them but looking back at on-coming traffic as you accelerate...into their rear-end? Your Volvo will save you. Guess how I know.
If you're feeling adventurous, I've found this situation to be a great time for adaptive cruise. I'll toss it on quick while looking over my shoulder. Less aggressive than the auto brake... I turn it on and pump up the speed on the steering wheel and so long as I keep a short follow distance (I always do) then it accelerates more than enough behind pokie mc pokeface (generally a Toyota or Subaru). Works pretty darn well.
 

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Why is it dumb? I’ve done it countless times to show friends how it works. With no traffic I’m a safe environment why would you not give it a try? Certainly doesn’t hurt the car.
Well, I mean test the actual features that involve another vehicle, like have someone drive at the rear fast, on purpose. Or approach another car and have it trigger to save you. Even with 2 of my own cars, that could get expensive real fast.
I am typically the guy that tests all that I can, within reason, and well I'm not sure how reasonable that would be.
I do check if AWD/4WD is working on every car I have with it, at least once per year. Gravel lot, grass, it is easy to tell for AWD, and if true locked 4WD, a tight SLOW circle on dirty pavement will tell you right away.
 

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If you're feeling adventurous, I've found this situation to be a great time for adaptive cruise. I'll toss it on quick while looking over my shoulder. Less aggressive than the auto brake... I turn it on and pump up the speed on the steering wheel and so long as I keep a short follow distance (I always do) then it accelerates more than enough behind pokie mc pokeface (generally a Toyota or Subaru). Works pretty darn well.
Yeah, that sums it up very well. And it does work pretty good safety wise!
Subaru drivers, talk about a binary crowd. 80% are either ex-hippie earthy old spinsters with POTted plants, or 20-25 year old hooligans that think they got the hottest car on the road, and usually make the most awful sound and look like crap. (the cars, well, the drivers too)
But the funny thing is, several family members have Foresters, and don't (quite) fit the mold, but close. One is my father in law, but he raced SCCA and also has a Porsche Boxster, and the other is my daughter after having a baby, but she used to have WRX...
 

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Well, I mean test the actual features that involve another vehicle, like have someone drive at the rear fast, on purpose.
I never suggested that. I was referring to try my example of in an empty parking lot release the throttle and stab the brakes as quickly as possible. Emergency braking functions really know differently then adaptive cruise control breaking in stop and go traffic, it’s simply more aggressive due to the circumstance.
 
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