Any 2020 owners had issues with the TSS pre collision warnings?

My 2020 has had the TSS Pre collision warning go off 2 times already. I only have 5k miles.
1st time was a heavy rain storm, I braked hard going down a hill, a large stream of water ran off the roof ,down the windshield, hood and the , dash lit up red,"BRAKE". I figured I knew what it was, just the water running over the camera and radar panel?
2nd time , I'm driving down a road in the dark, 30mph going straight, watching the road, and it happened again, for no reason whatsoever. weird?
I see that the sensitivity can be adjusted, so I set it down to the middle level.
Has anyone else have to change the sensitivity yet?

 

We have a 2020, we have not had this happen, you supposed the heavy rain would cause it to activate? If so, driving in heavy snow might cause the same thing. Hope not, we sometimes get heavy wet snow, and if it sticks to the radar or camera, we could be in for a surprise. We haven't driven in the conditions your talking about..... yet. (We have had other tests though)

 

Mine has gone of two times as well. Both during rain storms in braking situations similar to yours.

 

I have had no issues so far.

 

I've had it happen twice out of the blue. Normal sunny day, straight road, nobody anywhere near me. No idea what caused it.

 

There’s so many things that can trigger false warning for drivers assist systems in general. Semis, metal decked trailers, guard rails that start abruptly close to the edge of the road, lane markings, certain shadow can trick the vehicle into thinking they are lane lines, the height of signs, the distance of signs off the road way, exotic cars made from composites, weather (although most companies have a heating element that keeps snow/ice build up from forming in front of the sensor), bridges, intersections that have an oddly high amount of sewer caps, steep driveways, low angle direct sunlight in the cam, train tracks, puddles of standing water, etc. I deal with this type of stuff every day, it’s a constant ongoing battle to refine and advance the systems.

Also the TSS on the 4Runner is still Toyotas first generation of TSS, it’s ancient in terms of technology and its operation is pretty crude.

 

Thanx for the rundown, now it sounds like of matter of time! We have about 2000 miles on it without incident.

 

Brake warning has come on three times for me in 5200 miles. The first time only the message came on, and just for a few seconds. No audible warning (which I understand is the second phase of the system, the third being automated braking). It was night time and maybe a bit foggy, traveling maybe 40 mph on a 45mph road. But no obvious reason it should come on. I later realized that a few weeks prior to this event I had set the PCS to maximum sensitivity when I was playing with all the computer settings. So I then changed it to medium, which I believe is the Default setting.

The second and third times were well warranted. The second time a vehicle was heading straight for me on a residential street, basically going the wrong way in my lane. The system lit up and beeped, but took no other action and went off a second later as I took my foot off the gas and the driver turned back to his lane. There was no real risk of a collision since both I and the other driver were paying attention, but it made sense that the system activated and also that it did not apply the brakes on its own.

The third time was on the highway when traffic ahead slowed very abruptly. The system lit up and beeped. The driver (not me lol) was a bit distracted at that moment, so the warning was helpful. Prob wouldn't have crashed for real, but I guess I'd say it was close to being a close call. In any case, at that moment I was grateful for a system that honestly I would have deselected from the option sheet if I'd had the choice.

Question: you can shut off the system (though unlike the lane departure warning it comes back on every time you start the car). Buuuuuttttt, does shutting it off prevent all automated braking or does it only shut off the warnings? Does anyone know?

 

Mine came on just the other day. Was cruising along down the road and the person in front of me came to about a complete stop in order to turn right..... oh wait that’s what it’s supposed to do carry on guess mine is functioning properly

 

mine said it is disabled in super heavy rain and i was going about 70-75mph, in came back in like 2 min as soon as (probably) the sensor cleared

 

That's interesting. I'm going to keep a lookout for that in the next rain.

 

yes, interesting. maybe that provides a clue as to how to disable it completely (though I guess I wouldn't want a solution that filled the Multi Information Display with a constant warning message).

Anyone know if shutting PCS off disables automatic braking under all circumstances, or just the warning message and sound? Frankly I like having the warnings if there are few false alarms, but the potential for unneeded automated braking is unnerving.

 

The warning on the display goes away in a few seconds as I keep my speedometer there. It lights up yellow on the lower right of the dashboard.

 

Thanks for all the replies, glad i;m not alone .
Sounds like the TSS is not so great.
There will probably some sort of TSB in the future <I would imagine to fix the bugs in the system?

 

Alas, I think that's pretty unlikely. No doubt our software could be updated to get a bit smarter -- better algorithms / AI to reduce false alerts. But the system is inherently imperfect because it relies on radar and cameras that can be blocked or fooled. And AI software and computing power remains a long way from duplicating the abilities, knowledge and experience of actual humans. We immediately and subconsciously understand so many clues from other drivers and our environment that no computer is yet able to emulate. We have great predictive powers about how other objects and people will behave without even realizing how we know what we know. Computers not so much.

So I wouldn't count on more than very marginal improvements to existing systems. Maybe the new systems 10-20 years from now will be much better. Maybe.

 

The aren’t bugs, they are system limits. It’s driver ASSIST systems. You are still responsible to drive and control the car.

 

I've had 4runner, ford, jeep and a Mazda each having a different name for the safety crud. They all act out in heavy rain and especially wet snow on the highway.
Mazda was the worse. Driving up into the garage it would see the garage and stop. Dealer said they fixed it and I'll never hit anything again! Told the supervisor to drive it into the building and he wouldn't do it. They offered to set up a box in the lot to show me how it stops.....opps, didn't stop, lol

 

LOL. Awesome.

 

https://youtu.be/_47utWAoupo

 

opps

 

I just hit 5,500 miles this morning, but i've had the system kick on multiple times since new while driving in heavy Southern California traffic on the freeway. It's usually when the moron texting on their phone in front of me presses on their brakes every few seconds and braking is not needed (just coast for a few seconds before accelerating again), but the system seems to have a different idea of how to drive properly. I've tried to permanently disable the system by turning it off through the dash menu, but you have to turn it off every time you start the vehicle.

It's not as bad as other newer vehicles that also have that automatic start/stop BS in order to inflate the manufacturer's MPG claims, but it's annoying and startles me more when it kicks on than the situation at hand. I don't need my dash lighting up red and beeping while the Runner is nose diving on its own just because the program doesn't think that I'm paying attention or that I'm too close to the vehicle in front of me.

 

You may not remember this, but it was funny, Volvo but out some press release a few years back that starting in the 2021 model year every vehicle they will by either hybrid or full electric... the big ass asterisk they left out was that any gas engine with start/stop is now categorized as a “mild hybrid”.

 

Mine temporarily disabled itself during heavy rain while I was driving about 65 mph

 

That's funny. I haven't paid that much attention to Volvo, since their vehicles are ugly and overpriced in my opinion, but I did see that video above where the Volvo didn't stop as advertised when the video was first released.

 

I have had this as well.

as to the question about turning it off altogether. I believe turning the brake assist off turns the entire system not just the warnings off judging by an article I read about the new Land Cruiser. The author couldnt make it up a hill because the TSS kicked in and stopped the land cruiser going up a 4x4 path because of a log before the driver turned to avoid it. They turned it off and went up the same hill just fine.

 

I’ve got just under 1500 on mine and it’s turned itself off twice now while in heavy rain on the interstate. I did have it kick on and start braking when a tractor trailer changed lanes suddenly again on the interstate. Not a slam on the brakes instance but more of a firm brake. The biggest issue I have is when cruise is set (with and without radar activated) and you have to slow down and then regain speed the cruise surges until your back up to speed. Doesn’t seem very good for the power train but I’m not an engineer for the engine.

 

I'm no fan of these systems in general or the implementation of it on the 4Runner. But if it's activating frequently for you, especially if it's applying the brakes by itself (you mention nose dive) then I think there are only two real possibilities:

1. Your system is mis calibrated to be overly sensitive. If so, you may want to dial down the sensitivity in the PCS menu in your Multi Information Display. I think the default setting is Medium. Maybe yours is set on High for some reason. Either way, you may want to turn it down to Low and try that awhile before asking your dealer to check if something is amiss with your sensor or whatever.

2. You're tailgating. I'm really not trying to be a jerk here, but a properly functioning system wouldn't do what you describe unless you have a habit of following too close. No one on this forum seems to be describing what you're experiencing. There are reports of "ghost" sightings -- I had my brake warning light come on once for no good reason, back when my PCS was set to High. But I have yet to read about anyone having the system activate frequently in slowing traffic.

Pls keep us updated!

 

I'm at roughly 8800 miles and have experienced much of what has been described. Heavy rain and wet snow/ice will disable it. Have not had any issues with false warnings of impending collisions though. It has triggered a few times when someone has slammed on the brakes in front of me but it was warranted.

I did hit a deer but the way in which I hit him didn't trigger a warning or braking as he wasn't in the line of sight for the sensor.

The adaptive cruise can be a little aggressive with the braking so once it notices a vehicle and I won't be able to pass them for whatever reason, I cancel the cruise control until they are out of the way. You can also switch to regular cruise by holding the power button for 1.5 seconds.

 

Wish mine didn't have TSS

 

It really was a major factor in my decision to keep my 2011 and not buy a new 5th gen.

Between TSS, the air pump added to the engine, the change to blue backlighting inside, and a front end that looks like a pre face lift was stuck in pencil sharpener on an otherwise squared angular vehicle - none of those are things are I want, but none of those are optional either.