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Discussion Starter · #1 ·
1. I have a tendency to have my foot slightly on the brakes when backing up. Probably a habit I developed backing up in tight spaces. Does the RAB(Reverse Automatic Braking) work in this case ? Or does it work only if the foot is completely off the brakes ?

2. I have the same question for the Forward Pre-collision braking as well. Suppose the car is slowing down with an obstacle in front. Does the car slam the brakes if it finds I am not braking hard ?
 

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2021 Ascent Premium White (NEW!! 馃槏) 2015 Legacy 3.6R White (Former 馃槶) 2006 Subaru Impreza (Former)
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1. I have a tendency to have my foot slightly on the brakes when backing up. Probably a habit I developed backing up in tight spaces. Does the RAB(Reverse Automatic Braking) work in this case ? Or does it work only if the foot is completely off the brakes ?

2. I have the same question for the Forward Pre-collision braking as well. Suppose the car is slowing down with an obstacle in front. Does the car slam the brakes if it finds I am not braking hard ?
In both cases I've had my foot on the brake like you, and both of the features you've mentioned have worked like a charm in my case. (Both VERY abrupt stops, already some near misses with my new baby, because you know, people.)

However, I can't speak for other's experiences and I'm curious to see what people are saying.
 

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Discussion Starter · #3 ·
In both cases I've had my foot on the brake like you, and both of the features you've mentioned have worked like a charm in my case. (Both VERY abrupt stops, already some near misses with my new baby, because you know, people.)

However, I can't speak for other's experiences and I'm curious to see what people are saying.
Thanks, Pluckito1111 ! That does instill confidence. Will wait for other Subaru enthusiasts to comment as well with their experiences
 

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2019 Subaru Ascent Touring (Canadian Edition) -- Ice Silver Metallic
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1. I have a tendency to have my foot slightly on the brakes when backing up. Probably a habit I developed backing up in tight spaces. Does the RAB(Reverse Automatic Braking) work in this case ? Or does it work only if the foot is completely off the brakes ?

2. I have the same question for the Forward Pre-collision braking as well. Suppose the car is slowing down with an obstacle in front. Does the car slam the brakes if it finds I am not braking hard ?
Yep, foot on the brake for both situations - it kicked in because I was following closely and the guy in front suddenly came to a full stop.

Backing up I thought I still had some room, but the radars felt it was getting too close, and stopped me inches from a fence.

Seems to work well for Eyesight and rear radars.
 

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2020 Ascent Touring
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Yes to both.

Twice last week, I was crossing an intersection going straight and accelerated hard when the light turned yellow because a car was following me close. Just as I entered the intersection a car took a right on red in front of me and the brakes kicked in hard even though I was already back on the brakes. Luckily the car following me turned right (both instances) so I wasn't rear ended when the Ascent stood on its front bumper.

I always cover the brake when backing and the RAB hits the brakes when there's cross traffic half a block away.
 

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I find it kicks in sooner with my foot off the brake than if I'm slowing slightly with my foot on the brake. When I pull into the garage with my foot off the brake it will alarm. If I do so at the same speed but with my foot on the brake it won't alarm as soon.
 

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As others have noted, yes, even with your foot on the brake (and with the brake lamps lit, as shown on your dashboard display or by reflected light in your surroundings), those safety-mitigation features WILL engage.

HOWEVER.....

If you're crawling slow enough, you ABSOLUTELY -CAN- effectively "override" the system, and progress into/through the obstacle it senses.

Experiment for yourself - vegetation that encroaches or crosses a driveway, for example, is a great way to experiment and see what your systems will do and what you can do to override. Similarly, you can set up cardboard boxes to do the same.

I live in a rather densely populated "inner-ring" commuter suburb, so our driveways are narrow and garages small. I can absolutely drive both my Ascent and my wife's WRX -both EyeSight equipped vehicles- into trash-cans, shrubbery, fences...or even through said fence or through the back of my garage (should I desire to do so). 馃槄

Similar to the above but more focused on emergency evasive maneuvers, abrupt throttle inputs (sometimes) in conjunction with sharp steering inputs will also tell the collision mitigation system that the actions you're undertaking are intended to be emergency evasive, and will cancel the collision mitigation system. I have yet to be able to test this in reverse (er....probably won't get a chance to, ever), but there have been many instances where I was able to "tell" the flashing red lights "no, I know what I'm doing," and the pulsing of the ABS pump would cease, and power delivery be restored via the DBW, allowing me to proceed forward to evade. In each of these types of instances above, your continued input (i.e. by pinning the throttle to the floor) is telling the vehicle that you've determined that it's best to follow your actual inputs as the driver, versus its limitations as a driving/safety aid.

These conditions are actually all described in-detail in both our Owner's Manual (pages 362 and 367 for RAB, in the 2019 Ascent Owner's Manual) as well as the EyeSight Owner's Manual (page 81, again 2019 version). :). In the literature, for example, the scenario that's often referenced for driver throttle input override is if the vehicle becomes trapped on a railroad crossing - continued application of the throttle will disable the anti-collision system and allow the driver to proceed through the perceived obstacle.
 

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Discussion Starter · #9 ·
As others have noted, yes, even with your foot on the brake (and with the brake lamps lit, as shown on your dashboard display or by reflected light in your surroundings), those safety-mitigation features WILL engage.

HOWEVER.....

If you're crawling slow enough, you ABSOLUTELY -CAN- effectively "override" the system, and progress into/through the obstacle it senses.

Experiment for yourself - vegetation that encroaches or crosses a driveway, for example, is a great way to experiment and see what your systems will do and what you can do to override. Similarly, you can set up cardboard boxes to do the same.

I live in a rather densely populated "inner-ring" commuter suburb, so our driveways are narrow and garages small. I can absolutely drive both my Ascent and my wife's WRX -both EyeSight equipped vehicles- into trash-cans, shrubbery, fences...or even through said fence or through the back of my garage (should I desire to do so). 馃槄

Similar to the above but more focused on emergency evasive maneuvers, abrupt throttle inputs (sometimes) in conjunction with sharp steering inputs will also tell the collision mitigation system that the actions you're undertaking are intended to be emergency evasive, and will cancel the collision mitigation system. I have yet to be able to test this in reverse (er....probably won't get a chance to, ever), but there have been many instances where I was able to "tell" the flashing red lights "no, I know what I'm doing," and the pulsing of the ABS pump would cease, and power delivery be restored via the DBW, allowing me to proceed forward to evade. In each of these types of instances above, your continued input (i.e. by pinning the throttle to the floor) is telling the vehicle that you've determined that it's best to follow your actual inputs as the driver, versus its limitations as a driving/safety aid.

These conditions are actually all described in-detail in both our Owner's Manual (pages 362 and 367 for RAB, in the 2019 Ascent Owner's Manual) as well as the EyeSight Owner's Manual (page 81, again 2019 version). :). In the literature, for example, the scenario that's often referenced for driver throttle input override is if the vehicle becomes trapped on a railroad crossing - continued application of the throttle will disable the anti-collision system and allow the driver to proceed through the perceived obstacle.
Thanks @TSiWRX for that extremely detailed answer. Really appreciate it !
 

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^ No problem! Didn't want you to get caught-out because of lack-of-detail! :)

My narrow driveway with vegetation on each side was the cause for tremendous hilarity when I first got my '19 Touring, which was the first Subaru between myself and the wifey that offered the more advanced safety suite feature of RBA (my Ascent was our 8th Subaru since 2005, and her '19 WRX our 9th).....

I like to park "nose out" in case of emergencies, so when there's no traffic on our residential cross-streets, I hook a wide turn and reverse up my driveway and into my garage. Having to execute a 4-to-5-point turn to do the same once I've pulled past our house is marginally annoying. :p Over the years (our happy little home is a starter-home-turned-17-year-residence:ROFLMAO:), I've gotten pretty good at lining myself up for docking, and gunning it up the driveway.

You can imagine what happened when the wifey and I came home in my brand-new Ascent, when the RAB decided that a couple of overhanging leaves were an actual obstacle.

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I quickly discovered -because I didn't like the on-screen interface to turn off RAB- that by dropping vehicle speed to below 1 MPH, I can drive "through" the perceived obstacle without triggering the actual braking, even though "I've got good tone!"

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The same scenario plays out with EyeSight's forward collision mitigation - this is a route that I frequently take, "underneath" downtown CLE:

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See how even Google's mapping had some difficulties, there? :ROFLMAO:

That sharp left is pretty narrow when there's oncoming traffic (especially if it happens to be a commercial vehicle), so occasionally, EyeSight likes to yell at me that I'm gonna die, and more rarely even starts the ABS-intervention. A flick of the wheel and a jab at the throttle kicks the system out of that model, and allows me to complete the turn without having to worry about a following vehicle rear-ending me.

I love all the safety features that's on our newer Subarus...... But it doesn't mean that they're perfect. :)
 

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If you're crawling slow enough, you ABSOLUTELY -CAN- effectively "override" the system, and progress into/through the obstacle it senses.
It will auto-disable after the first "hit" while backing up a trailer, too...it stops and accelerating backward turns it off, at least it does for me. I back my trailer into our driveway every time after I return from I mowing at our old property. Beep/Bang and done. :) :D
 
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As others have already stated, "yes" to both, unfortunately. I find it annoying a) when backing into my garage and it slams on the brakes, and b) when trying to pass a slower car right in front of you and it brakes on your behalf - this one is a little disconcerting at times.
 
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