HARD Braking

[fasteddie2015]

The complexity of my 2015 LC still has me on the learning curve. Here’s the latest. It’s happened twice now. First time I wanted to test the radar/cruise control. Second time it happened on its own with cruise on but no speed set. Both times approaching slower traffic straight ahead.

Driving along at 70 or so (speed limits are high here). Suddenly the LC slams on its brakes to the max. Second time seatbelts both sides are grabbing like they’re reeling in an angry tuna. I had my foot on the brake. Not sure if I hit at the same time or in reaction to the incident. Took pressure off the brake but the braking continued for a second or 2 before the LC let go of the brakes.

Good news is that the brakes stop amazingly well! Bad news is wtf happened?!?! Is this normal and what condition caused it?

I left the cruise off after the most recent incident. The 2 incidents were a month apart. Also, I could have slowed safely with moderate braking.

 

[Sandroad]

Sounds like the brake assist worked.......
(And, BTW, not part of cruise control)

What is Toyota Brake Assist?
Toyota Brake Assist is a built in, passive safety feature included in the Toyota Star Safety System designed to offer support in the event of emergency braking. According to a study performed by Toyota, nearly half of all drivers don’t step on their vehicle’s brakes hard enough or quickly enough to completely stop the vehicle in the event of an emergency. That’s where Toyota Brake Assistcomes in.
The Toyota Brake Assist is able to detect the driver attempting to make a panic stop. When this occurs, it supports the driver in braking, adding more power to the brakes.
When you’re in a situation that requires emergency braking, you’re likely to quickly step down on your brake. Brake Assist is able to detect panic braking based on the force that is applied to the brake pedal and how fast the driver is stepping on the pedal. When that happens, the system is able to recognize your sudden braking and apply additional pressure to the brakes.
Once you’ve come to a stop, Brake Assist will lessen the braking power and regulate the brakes after you release your foot from the brake. After that, you’re able to drive your vehicle normally.

 

[GoISU]

It seems to be watching for a quick tranition from gas pedal to brake pedal. I have triggered it before, usually when you space out or are distracted for a second and you get off the gas pedal and stab the brake. It seems to operate independent of the radar system and it makes sure that the system applies max braking power. It will continue to slow you even after you get off the brake. I have triggered it and then tried to get it to release as I wasn't as close to a rear ender as I initially perceived. A dab of gas seemed to cancel the response, you don't have to go all the way to a full stop. I have never tried to induce this response but I think it would be fairly easy to do.

 

[TeCKis300]

When was brake assist introduced to the 200-series?

 

[Markuson]

And...4th paragraph here:

Toyota Boosts Price of 2008 Land Cruiser

The latest news from the automobile industry.

www.caranddriver.com

 

[Fisher23]

The complexity of my 2015 LC still has me on the learning curve. Here’s the latest. It’s happened twice now. First time I wanted to test the radar/cruise control. Second time it happened on its own with cruise on but no speed set. Both times approaching slower traffic straight ahead.

Driving along at 70 or so (speed limits are high here). Suddenly the LC slams on its brakes to the max. Second time seatbelts both sides are grabbing like they’re reeling in an angry tuna. I had my foot on the brake. Not sure if I hit at the same time or in reaction to the incident. Took pressure off the brake but the braking continued for a second or 2 before the LC let go of the brakes.

Good news is that the brakes stop amazingly well! Bad news is wtf happened?!?! Is this normal and what condition caused it?

I left the cruise off after the most recent incident. The 2 incidents were a month apart. Also, I could have slowed safely with moderate braking.

There is an adjustment for that to the right of the steering column . you have it set too high.

 

[chilibit]

When in radar cruise mode the system will occasionally see or imagine a threat and go into panic stop mode.
The key word here is imagine which machines don't do---but you get the idea. When this happens it is just like the
Autobahn in Germany---the real threat is now in your rear view mirror.

 

[cboyd]

There is an adjustment for that to the right of the steering column . you have it set too high.

Really? Where is that, I’m not seeing it.

 

[Volunteer]

At our monthly club meeting yesterday @kjnarmyfj was saying he was having similar issues with the braking in his 2015.

 

[kjnarmyfj]

Mine does it radar on and off , random
Often , I was going 30 mph coming up to light. No one in front me
Yesterday slowly eased on break and BAM screeching hault ! It’s has done it to me at 65 one day and almost made me get rear ended. Mine will come to almost a complete stop 5 mph . To the point where I’m always scared to hit the breaks . My wife hates my 2016 land cruiser . Because last 3x she has rode in it it has done this , one time making a coffee fling all over every dammthing . Almost at the point of selling it and getting a Trd tundra , for a 90k truck this is dumb

 

[rockcruiser915]

Mine does it radar on and off , random
Often , I was going 30 mph coming up to light. No one in front me
Yesterday slowly eased on break and BAM screeching hault ! It’s has done it to me at 65 one day and almost made me get rear ended. Mine will come to almost a complete stop 5 mph . To the point where I’m always scared to hit the breaks . My wife hates my 2016 land cruiser . Because last 3x she has rode in it it has done this , one time making a coffee fling all over every dammthing . Almost at the point of selling it and getting a Trd tundra , for a 90k truck this is dumb

I know exactly what you're going through. Exactly. My wife freaked the first time the LC stopped on its own. I did too. I thought I was nuts, but I wasn't. And neither are you. But don't give up on your LC just yet.

It's possible to activate the pre-collision system (PCS) under both driving conditions (with or without cruise control activated). Either way, its the PCS that's causing your vehicle to stop suddenly. One situation I've become aware of is when I'm driving in the fast lane and the freeway curves, PCS will sometimes detect a slow moving vehicle in the lane next to me and activate. Give a little gas and the event stops. You can control the distance between you and the vehicle (or object) in front of you before PCS kicks in. Call it the "sensitivity" setting (I know that isn't from the manuel, but I'm too damn lazy to go look right now). You can also control the distance before your vehicle will begin to slow to match speed of a vehicle in front of you while using active cruise control.

It sounds like you need to adjust your PCS and possibly active cruise control settings... once you do that you'll need to figure out what situations cause it to activate and how to appropriately respond. Of course, you'll have to explain to your wife (as I had to) that the feature is there to save your @ss. Check off all those boxes and I think you'll fall in love with your vehicle all over again.

I know I did.

 

[Fisher23]

Really? Where is that, I’m not seeing it.

On mine it is this button here that is just to the right of the steering column.
In the picture the button top right has like 3 settings, I had to adjust to the various driving conditions and leave it low unless I'm out in the middle of nowhere.

 

[slowride]

"Suddenly the LC slams on its brakes to the max. Second time seatbelts both sides are grabbing like they’re reeling in an angry tuna."

LOL!!!!! That's the BEST description of an "unexpected event" and the LC's surprise the front passengers reaction...

We've had this happen to us now three or four times...

Luckily it hasn't caused any serious problems for us or anyone behind us...

It sure would be a scary time if those angry seat belts didn't release after a few seconds...

Always, glad to see the Cruiser is on guard to protect its precious cargo...

 

[fasteddie2015]

Well, on my 2015 I've got that panel to the rt of the steering wheel, but no switches in it.

 

[fasteddie2015]

Thank you. I'll be here all week.

 

[Tex68w]

I've never experienced it in our 200 but it has happened in every single FJC and 5th Gen 4Runner I have ever owned. It always scares the ever living crap out of me and it is always an over reaction for the situation but I guess it beats the alternative.

 

[kjnarmyfj]

its dumb ! ... I have a fused foot and my wife blamed it on me but im like yo its not !

 

[PDoyle]

I'm looking to adjust the pre collision braking on my 14. Is there a button?
I can't seem to find an adjustment anywhere.