Radar Controlled Cruise Control question

This is my first vehicle with RCCC. I noticed on a trip over the past two days that if someone merges in front of me or if I'm in a turn and a car is slightly ahead of in the adjacent lane, that the system executes a pretty aggressive slow-down on the 4Runner. My question is, when this happens, do my brake lights come on?

The reason I ask is that the action is very much like me hitting the brakes pretty darned hard, and if I was behind me, I would want to see brake lights when that happens. Any one able to confirm if they DO or DON'T activate when this happens? If the do not, I can foresee some issues down the road.

 

If the truck applies the brakes, yes.

If it uses engine compression by downshifting no.

From what you said, sounds like it applies the brakes.

Also, the behavior you’re describing is what happens when a heavy, primitive vehicle is given new technology it was never designed for.

 

Something else with this system I wasnt aware of until i got to that part of the manual is the distance the radar reads and adjusts your speed is adjustable—- basically car lengths. The default is what seems like a football field length which is so far it invites people to cut in front of you.

to answer your question though- yeah if the vehicle auto brakes the brake lights also auto illuminate…

 

We have this on our Rav4 Prime, and I can say it acts the same way, annoys me, but helps keep the speedo in a reasonable place.

 

yeah i find that it can be too aggressive at times...ive had similar tech in Audi and BMW vehicles that was more "intelligent" and less aggressive unless it really deemed the need to in case of crash at high speeds etc... at the end of the day it is nice to have on the 4runner and definitely appreciate it on long highway drives where i don't always have to tap the brakes or cancel the cruise control constantly ..

 

I found my 2019 Tacoma would react aggressively.

 

Is there a readers digest version on how to turn this feature off?

 

You can also turn it off and use normal cruise control if you like. Just push and hold the cruise control ON button until message that the radar is turned off shows up on information display.

 

So, depress the button on the stick until I get a dash display?

 

Yep

 

Muchos grassyass

 

When the radar cruise slows you down, does it resume speed automatically when the distance to the vehicle in front of you increases?

No such newfangledness on my 4R, so I'm just curious...

 

Yes, it hammers on the throttle pretty hard to get back up to speed.

 

Yeah hammers it no doubt.
Very little tolerance for deviation above or below set speed.

So a big part of my daily drive to work is a nearly flat stretch about 30 miles long with no stoplights. 1/2 is 60mph and 1/2 is 55mph.
Ive been experiment using cruise and driving manually. I’m finding cruise is about 2mpg worse than driving manually.
Anybody else see this with using cruise?

 

Yeah, I've always gotten worse gas mileage using cruise control in normal conditions. Too many hills and changes in traffic speed that you can anticipate, while the system ahs to react (less efficiently).

Best use case I've found for smart cruise control is those sections of highway with a single lane due to construction, where you end up going 50-55 due to trucks.

 

Ditto. I don't think cruise increases gas mileage if your normal manual driving technique isn't weird. In fact, I'm not surprised that it reduces it.

I would like to see a controlled test of using Radar Cruise, vs Non-Radar Cruise, vs Manual and see if there's a difference between the 3.

One other point... I was driving in Northern NJ the other day during a snowstorm, and got a dash-light and message saying that my collision avoidance system was unable to work due to the "sensor needs cleaning". During this, I also could not engage Cruise control at all. I pulled over and found a layer of snow-slush-salt on my sensor on the grille. Wiped it off and the fault cleared. I wish I had known about holding the button down to use "normal" cruise... to see it it would bypass the fault.