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At speeds above 30mph, the rear tires would lock up and the car would likely start yawing into a skid.
I've tested engaging the e-brake while under way in a parking lot at low speeds. It was pretty dramatic even then. The system has no modulation. It just puts the brakes fully on when activated.
It's possible the G5 and G6 have more developed systems, but I've never seen any mention of it.
I've did the same with my gen 6 Legacy, with the same results. A very slight delay and then eye popping full on max brakes, screeching to a stop. I would not want to do this at highway speeds.
 

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This is good information about the E-Brake. At least the old style manual E-Brake, you could modulate it. I guess it makes sense that the E-Brake is an entirely separate system from the ABS brakes. But still, I think I will try to remember to downshift first. Though, I have never had to use an emergency brake in my life. As a parking brake, yes. Remember the old brakes on clunkers, when they got spongey? At least you could pump them though.:)
 

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The attachment in this post describes exactly how the e-brake system works in a Gen 5. This is likely the same for Gen 6 since, AFAIK, they use the same EPB system (which was new for 2015 models):
 

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The attachment in this post describes exactly how the e-brake system works in a Gen 5. This is likely the same for Gen 6 since, AFAIK, they use the same EPB system (which was new for 2015 models):
Awesome post and attachment, thanks for this.

I find it amusing that someone, right after the post with the attachment, posts that no car has ever had an emergency brake and no car maker has ever called an item an emergency brake, ignoring that right in the attachment that contains a page from the owner's manual Subaru calls the feature out for having "an emergency brake feature" and then describes how the emergency brake feature works.

After reading the attachment I feel much better about the e-brake. Very cool.
 

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Interesting that when the car is moving, if the EPB is activated, the ABS system kicks in, applying braking at all four wheels, until the car is near stopped at which time the EPB, which operates only on the rear wheels, takes over.

That could mean the rapid deceleration in the video might have been the EPB activating at speed. And the fact that after the car stopped it couldn't be moved before restarting the engine might be consistent with the ABS dropping the "hold mode" (due to the restart) and the EPB releasing as it would normally when the car is put in D and the accelerator pressed. (But that begs the question of why the hydraulic system would continue to be applied when the EPB had, or should have taken over.)

I had thought the more recent discussion about items on the dash affecting Eyesight was pointing in the right direction, but now it's back to a toss-up between that and rogue EPB application.

In any event, I learned something new about the EPB application while moving.
 

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2020 Onyx
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I always thought of it as a parking brake and when people started saying E-brake I thought it meant electronic brakes. It turns out it means emergency brake. When the terminology changed I don't know.
 

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2021 OB Touring, 2011 OB Premium
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At speeds above 30mph, the rear tires would lock up and the car would likely start yawing into a skid.
IMHO, with full activation of the braking system, there "should" be no yawing or loss of control due to skidding. The Outback has an anti-lock braking system, which applies the brakes to all four wheels fully, but also allows the wheels to turn, albeit, slowly. This keeps what is called rolling friction and allows for some driver control/steering under the braking conditions, rather than simply locking up the brakes. I hope this explanation helps a bit.
 
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IMHO, with full activation of the braking system, there "should" be no yawing or loss of control due to skidding. The Outback has an anti-lock braking system, which applies the brakes to all four wheels fully, but also allows the wheels to turn, albeit, slowly. This keeps what is called rolling friction and allows for some driver control/steering under the braking conditions, rather than simply locking up the brakes. I hope this explanation helps a bit.
If the emergency brake (or parking brake, whichever you wish to call it) is activated in an emergency stopping situation such as loss of primary braking system, the ABS is not a factor. And no, ABS does not apply 'the brakes to all four wheels fully', the ABS can kick in at any brake pressure is being called for by the driver as long as a wheel stops moving when it shouldn't be but it wouldn't increase the pressure.
 

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Did you see the attachment originally posted by @ammcinnis? It says that in 2015 with the electronic parking brake, ABS is involved.

Rectangle Font Line Slope Parallel
 
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IMHO, with full activation of the braking system, there "should" be no yawing or loss of control due to skidding. The Outback has an anti-lock braking system, which applies the brakes to all four wheels fully, but also allows the wheels to turn, albeit, slowly. This keeps what is called rolling friction and allows for some driver control/steering under the braking conditions, rather than simply locking up the brakes. I hope this explanation helps a bit.
The poster was refering to the emergency brake, not the ABS brakes. According to the document posted, the emergency parking brake (EPB) acts independently of the ABS. When you pull the lever, and you are going fast enough, the system will first try ABS (all wheels) until you are slower and then go to EPB. If ABS fails it goes to EPB immediately. EPB will lock (and unlock) the rear tires. It seems that the electric motor for EPB is rudimentary compared to the ABS hydraulic pump and can only lock or unlock the rear breaks, but it does this many times while it monitors the wheel speed sensor. Likewise, the ABS functionality is also reduced in that once the system determines the maximum brake pressure before lockup (on all 4 wheels), it then holds it there. Which might be a problem if your car then comes up on a more slippery surface. In normal ABS mode, the system is continually monitoring the wheel speed sensor. It seems that the EPB lever, when held, will attempt to stop the car as fast as possible, with at least some locking occurring.
 

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Did you see the attachment originally posted by @ammcinnis? It says that in 2015 with the electronic parking brake, ABS is involved.
I did not got see that other thread. I have to wonder though - if you're needing the emergency/parking brake you're typically going to have no brake fluid as even if you lose assist you can still press on the pedal and get some brake force, there aren't too many other failure modes, if there's no fluid how effective will the ABS pump be anyway?
 

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I did not got see that other thread. I have to wonder though - if you're needing the emergency/parking brake you're typically going to have no brake fluid as even if you lose assist you can still press on the pedal and get some brake force, there aren't too many other failure modes, if there's no fluid how effective will the ABS pump be anyway?
The ABS would be useless in that case and the system will go immediately to the EPB.
 

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The scenario we're describing is activation of emergency braking, either via eyesight error or the emergency parking brake, which could be due to a defective switch or some other issue. Now when it comes to the emergency brake, pulling and holding the switch upwards isn't something you do subconsciously or without noticing it, unless somehow something hooked on to it which would be very hard to do even on purpose, so I think unless something extraordinary happened, we can rule out inadvertent driver activation of it. Maybe if there were a child in the front passenger seat who said "what does this do?"
 

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Yeah, while unlikely, it's possible that something could somehow lift the EPB switch (something catches it or gets jammed underneath). In the LegacyGT thread, the OP does in fact say that his whole family was in the car, kids in the back.
 

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on my 2011, I've pushed the electronic emergency brake before and it doesn't skid nor is it eye popping. It modulates itself and it would never stop as fast as the video shows.
 

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on my 2011, I've pushed the electronic emergency brake before and it doesn't skid nor is it eye popping. It modulates itself and it would never stop as fast as the video shows.
But have you tried that at highway speed on a Gen 5 Outback? I doubt many have.
 

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As far as I know, the 4th gen did not have anything more than the traditional mechanical rear wheel parking brake system, but with an electric motor (and some electronics) instead of a lever in the cabin, acting on a pair of cables, to pull the parking brake shoes against the rotor drum. The 5th gen has the system described in post #30 above, which, at highway speed will apply the hydraulic brakes at all four wheels before engaging the parking brake system, which still acts only on the rear wheels. I would imagine it's the hydraulic 4-wheel hard braking that makes a significant difference in the rate at which the car slows.
 

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If that's what they have, sounds like a lot better solution for an emergency. Although I'm sure it would be pretty terrifying to have full power brakes by pushing a button.
 
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