Lane Tracking Assist Issue

BTW, I did take my care out on a 200-ish mile trip today and fiddled with the Lane Change Assist. I still can't get it to work reliably, but can get it to work occasionally exactly as you'd think. I didn't get to test it too much due to way too heavy traffic and not wanting to experiment with any cars near me. It does look like you have to use just the press-but-not-click turn indicator for it to work. Still not convinced, and it will be a while before I can play again.

will

 

In Finland I think it's going to be particularly poor because we have seasonal road limits. All the national roads switch between 100km/h in summer and 80km/h in winter. The signs are changed accordingly (there's a job for someone!). But from what I understand, Toyota's system has a strong tendency to fall back to map data, and I don't believe that contains any seasonal info, and the EU law does not require the car to understand time of year limits.

So what I'm expecting in winter is for it to show 80 for a bit from a sign, get bored, go back to the 100 on the map, then repeat. Let's see... (And lot of the time the signs will be illegible due to snow...)

Another point is that type approval is carried out in one country, so the Prius was only actually tested for Belgium with Belgian signs...

 

I've played with it a couple of times. You have to hold the indicator in the first position long enough for it to start, and you have to keep hold of the wheel, but not initiate the change before it does, and not fight it. Bit weird.

 

Thanks KMO: I think between accidentally clicking the turn indicator still and maybe not holding it long enough I'm not doing it right. My next mini-trip is next week and think I'll go back and re-read that part of the manual with your advice in mind. This one definitely isn't intuitive!

will

 

This seems to be the emergency driving-stop system kicking in because the car thinks you may be unresponsive. In fact, it will bring the car to a full stop if you don't take any action. How it operates and the various warning phases are explained in the owner's manual.

2024 Prius Prime owner's manual

 

All US Prius and Prius Prime models have FCTA (front cross-traffic alert), and all US Prius Prime models have traffic-jam assist, which automatically steers the car around other cars in slow traffic.

https://www.toyota.com/priusprime/2023/features/mpg_other_price/1235/1237/1239

You don't need the front side radars for FCTA. I don't know if the US models have the front side radars or not, but the system works without them with slightly different specs.

I wish they could update the firmware on Gen 4 models to make them TSS 3.0, which is all it takes because the hardware is already there, but of course, Toyota, unlike Tesla, is not good at firmware updates.

 

Ah, thanks, I missed it on that page, cos I was looking for 'FCTA'.

But Hammersmith confirmed above his non-Prime Limited doesn't have it. So Prime only, like the traffic jam assist.

Source? The fact there's only one spec shown in the Prius manuals suggests there's no FCTA-without-side-radar combination in the Prius. Whereas other functions like PCS do show different specs with and without front side radar.

FCTA is specifically an early warning, unlike the PCS or PKSB, suggesting it's not worth it without the radar.

 

Hmm, indeed the Prius HEV does not have FCTA according to the specs on the Toyota website, but Prius PHEV has it.

For me, it's a moot issue because if I buy a Prius, it would have to be a PHEV. Some posters here will not even buy a PHEV anymore but would only settle with a BEV. Nevertheless, this is another reason for me not to consider the Prius HEV. @daisy555, here is another thing for you to worry about.

Regarding front side radars, I was looking at intersection-collision avoidance support for with and without them in the owner's manual. I guess FCTA implementation is somewhat different. In any case, I am guessing that the PHEV has front side radars anyway because of the traffic-jam assist function.

 

This is a follow-up to the earlier traffic about Lane Change Assist with Planetarian and Blackat. I am on another mini-road trip starting today and played with LCA and finally have it sorted out, no surprise that it was indeed user error.
Lesson 1: Only do the temporary push (don't click) the turn indicator
Lesson 2: Hold the turn indicator in that temporary push until the car starts the lane change. I was just pressing for ~1 second or so.
Lesson 3: I release it when the car is straddling the line being crossed.

Lesson 1 was a muscle memory problem, lesson 2 is probably covered in the manual and I should re-read it again, I was in "firehose" mode reading it the first time.

Fun side note: My trip today was on I-70 over the Eisenhower tunnels in Colorado (from 5000 to 11,000 feet). The Prime was a dream! I just sent cruise and it went. The engine never even sounded stressed the entire climb. The battery clearly didn't last long and Lake Keep Assist wasn't that great on the sharper turns at interstate speeds, so I "switched to manual" for steering pretty quickly. For reference, this is my first car with more than 100HP, so no car before could keep up with the speed limit to the top. My Gen1 could until the battery ran out, then choked.

will

 

IMHO the Traffic Jam assist doesnt need additional outside hw as its just a level 2 "plus" feature dealing more with driver monitoring.
Additionally to FCTA and the LCA the side short range radars (SRR) might be used too to detect physical lane barriers as part of LDA, something only TSS 3.0 can do. Before lanes where detected via camera only. Perhaps even the LTA might check cars on the side via SRR, e.g. when overtaking on a highway

 

According to Toyota USA, Gen 5 Prius Prime comes with front corner radars:

Prime Convenience

Prius Prime will also come with some additional features made possible by the equipped front corner radar sensors and a driver monitor camera. These features include Lane Change Assist, Front Cross Traffic Alert, Advanced Park, and a first among the Toyota line-up, Traffic Jam Assist.

Lane Change Assist works in collaboration with Lane Tracing Assist, meaning it also only operates when DRCC is activated. When a driver partially engages the turn signal, the system sensors monitor to confirm there are no vehicles in the path of the lane change, and then provides steering support into the new lane with the driver’s hands on the steering wheel.

Front Cross Traffic Alert uses the front corner radar sensors to detect vehicles approaching from the side in situations such as when slowly approaching or stopped at an intersection. Arrows are displayed to warn the driver, and if the driver attempts to proceed when there’s cross traffic, the vehicle provides an audible alert and warning on the MID.

Advanced Park executes the necessary steering and brake controls to navigate the vehicle into a selected parking space. Advanced Park is capable of parallel parking, backing into a perpendicular parking space, and can assist in exiting a parking space, all hands-free under the driver’s supervision.

Traffic Jam Assist is a driver-assistance feature that helps ease the burden of the stressful stop-and-go of a traffic jam. With an active Drive Connect subscription or trial, this system provides hands-free control of the vehicle steering, braking and acceleration at speeds under 25 mph under certain conditions. This system is designed for limited-access roadways, and the driver monitor camera must confirm the driver’s eyes are on the road for hands-free operation. The required Drive Connect subscription for Traffic Jam Assist comes as a 1-year trial on the XSE premium grade as well as the XSE grade equipped with the upgraded 12.3-inch multimedia screen. The SE grade and the XSE grade equipped with the 8-inch multimedia screen are Drive Connect capable, Traffic Jam Assist requires an activation of this service.

Prime time for more EV miles with the all-new 2023 Prius Prime—Toyota USA newsroom

 

Did anyon claim otherwise?

I dont think Advanced Park uses the side radar to detect parking space - the system is mostly camera based besides using the USS. But Im curious for any technical specifications.

Additionally it seems weird in your list given its available to normal Prius as well?

Edit: Aisin is the supplier for the system - they mention no radar. Would be an integration hell anyway:

 

@KMO did.

For advanced park, what is stated about radars in the press release could be erroneous. Nevertheless, since they are 77-GHz millimeter-wave radars, they should be able to resolve down to about a centimeter and can be used to assist with parking in principle. Cameras and ultrasound sensors are used for sure.

 

I was only doubting any US models having FCTA at all, but you already found that info a few posts back. It was only you thinking front side radar fitting was somehow decoupled from FCTA.

 

The front radar is definitely used for parking (though that isn't much in debate) based on some driving yesterday. I'm up in the Colorado mountains in mucky snow/sleet and while putting around a parking lot I got all sorts of warnings that the parking assist feature was inoperable due to sensors being blocked due to ice. The warnings at me the whole time I was puttering around the lot were a bit tiresome, bit one cool feature was it puts up a graphic of all the sensors showing which ones are blocked. I just wiped it off once parked so it wasn't an issue when I left.

will

 

That's not the radar though - that's the parking sensors. The radar's the block in the top grille underneath the Toyota badge.

(It can complain about both while driving in snow/ice. Not sure why I care about the parking sensors when driving at speed...)

 

Somewhere on this board, you explicitly said that the US Prius Prime models did not have front corner radars—so, that was misinformation.

After you said that, I did some research on that and found out that even models without front corner radars had the intersection-collision protection, including for cross traffic. However, I later found out that this was separate from FCTA.

Toyota press release was the final nail in the coffin that cleared things up for once and for all.

 

Yes, those are the ultrasound-sensor buttons. I recently got a warning when I hit a flying flimsy plastic bag on the freeway—I am not sure if/why it caused it. Perhaps it temporarily covered one of the sensors.

 

No, I didn't. So, that was reading comprehension problems.

 

Yes, you did:

Lane Tracking Assist Issue | Page 2 | PriusChat

You also said you were not sure the US Prius Prime had front corner radars on some other thread but I don't remember exactly where.