Cruise Control Not Deactivated By Braking

I understand your point, that it may have been designed this way. I think though that it is also a very fair point to criticize this design. I agree with all the others on here that believe this is a design flaw and should be removed.

ANY AMOUNT of pressure on the brakes that can be sensed by the car should by design disable the cruise control. I believe this would be a safer design and more intuitive. Yes, I know the control stick cancels it too, but that doesn't mean it's a good design.

 

Minor switch adjustment.

 

I have noticed this also. When I am using it, I think it is a great feature. At first, it seemed different, but once I got used to it, I use it all the time now. If I need to slow slightly, I know that I do not have to reset or resume cruise, just let off the brake and you are back in cruise. I think you just need to get used to the new system.

 

My experience with the Prius CC came when I tapped the breaks to deactivate the CC when I realized I couldn't change lanes to pass because another car was coming up in the left lane at 90mph. Since the first tap didn't work, I did it again, and again until I had to slam on the breaks to avoid a crash. After that I started using the CC stick. The problem with the stick is it isn't always accessible when you're going around a bend in the road... the break pedal doesn't change position. If you have to move your hands to adjust for a bend in the road the stick can end up out of reach (i.e. between your legs).

If this is how the system is "supposed to work" it's a dangerous design change that should be spelled out in the owners manual and again in the DVD. To deviate from the standard that's been around for 25 years without letting people know that the change is intentional, is blatantly dangerous.

How many crashes are necessary before this gets recalled?

 

You should also be aware that your brake lights may not be coming on soon enough. According to the "head mechanic" at the local Toyota dealership they use the same switch. In fact their excuse for not adjusting mine was if they set the switch for the CC the brake lights would come on to soon. I think what that really means is that they didn't want to fool with it. What the heck I already paid for the car didn't I? why should they try to make me happy? Anyway I know where the switch is, under the dash activated by the brake pedal, I'll try to do it myself.

 

Such is the world of automotive service.

 

The brake light light switch is activated by the brake pedal arm moving away from the switch. The brakes are activated by a different mechanism that generally requires more movement of the pedal.

My guess is that the position of the switch is too low, which means that actual braking occurs before the pedal has moved enough to activate the switch.

The switch position needs to be adjusted so that the lights trigger with the minimum movement that still allows the lights to turn off when the brake is released.

Given that Toyota is facing a major recall because of jammed floor mats and/or defective accelerator pedals, you'd think they'd jump on anything that even hints of unintended acceleration. Escalate your complaint to motivate that do nothing "head mechanic".

 

I don't think it could make the brakes work any differently, it's just a switch that cancels CC and lights the brake lights. It has nothing to do with the actual operation of the brakes. I crawled under the dash and looked at it. The switch can be adjusted by screwing it in or out as RobH said but it's a bit hard to get at, it would need to be screwed out (CCW) a turn or so to come on sooner. Mine isn't as bad as darogers so I haven't gotten to it yet.

They should have used two separate switches.

 

I have seen this issue on my Prius as well and am quite startled by it. Any TSB/resolution that people are aware of? I have looked thru the manual and this "feature" is not documented which then begs the question if this was intended or not. A light touch (at least before regen/braking begin) on the brake pedal should cancel CC as well as flash the tail lights like it does on most other cars such as my Camry and Accord...

 

I never had mine re-engage after braking, but when new, the car contined in cruise until I put quite a bit or pressure on the brake, which then caused the car to lurch annoyingly. It was obviously a simple adjustment problem with the cut-off switch.

The original dealer said the CC was within specs and would not adjust, so I went to another dealer who did it no problem. I could have adjusted it myself, too, just didn't get around to it. Works perfectly now, just a feather touch on the brake disengages CC, the way it should work.

See other threads on CC cut-off switch adjustment.

 

I NEVER use the brake to disengage CC. I always pull the lever forward. In fact, with CC activated, I use the lever like an accelerator: pull it forward to release, flip it up/down to increase or decrease speed, etc. Using the lever, CC seems very responsive. I'm going to try the slight brake pressure and see what happens with my CC.

 

I only disengage with the brake in an emergency. The little stalk is so easy to use that I do much like you, using it like a hand throttle.

Tom

 

I used to have the same problem as the CC didn't cancel with light braking. It is a common problem with Gen III Prius if you search on the Internet (on Toyota's recall page). I asked a Toyota adviser but he hasn't even heard of this problem. So, I took off the black plastic cover (where the tires pressure reset button is), you should see a green switch contacts with the brake pedal arm. Just move the green switch up a couple notches at the point where brake lights turn on with a slight touch on the pedal. My CC deactivates the way it should without delay. I believe it is safe to do it yourself.