Disengage cruise control with a breath on the brakes. A final solution?

Excellent information! I might try this over the weekend. I appreciate the effort to post pictures!

 

Great info; thank you. I was afraid this was going to be an example of locomotive breath.

 

The term "Final Solution" in the title gave me a little pause.

Tom

 

Good to know. Your pictures are great.

 

Your "fine adjust" appears to be for the master cylinder pushrod,
having nothing to do with the brake light switch itself. This
begs the question, does the CC release based on input from the
light switch, input from the master cylinder pressure sensor, or
perhaps both? You probably *don't* want to be messing with master
cylinder position adjustments just to achieve this small fix.
.
_H*

 

I was just about to say the same thing. That is not for the light activation.

 

I think it may work fine. The adjustment looks like it moves the brake pedal arm in or out which will effect the position of the flat piece that contacts the switch. Even though the adjustment is located on the rod that goes to the master cylinder it appears that the adjustment shouldn't effect the position of that rod, it changes only the position of the pedal arm. The actual position of the brake pedal at rest will change but it would only move by such a small amount as not to be noticeable.

 

Are you saying (in other words) that you used the brake light switch (Green Plastic guy) as a 'coarse' adjustment and tweaked the pushrod as a 'fine' adjustment?

I only adjusted the brake light switch, and found that satisfactory for what I wanted to accomplish - the graduations on the outside seemed sufficient to get it to where I needed.

But - it's always nice to know that if I want to get really detailed, I can spend more time contorted under the dash to get it 'just so'.

The pics are great. I wish they were here when I did mine!!!!

 

Thank you for this post. Among the many things my husband does not like about the Gen. III (as opposed to our Gen. II) is the CC giving us a jolt when it finally disconnects because he has to press on the brake so hard to disengage. Can't wait to show him this fix. It's totally safe, right?

 

Lawyer Speak: "Although there is much evidence to support the safety of this modification, I don't think any of us here can (or should) advise that it's "totally safe".

Based on most of our experiences, it appears very safe. Keep in mind that the brakes are a safety system component of the vehicle. In this case, you'll be adjusting a switch that -to the best of my capability to determine - turns on the brake lights, and disengages the cruise control. At this point, I have no reason to believe that the modification effects any other vehicle behavior.

That said, the Prius is quite a complex vehicle, and there may be other interactions of which I (we) are not aware, and which may have an influence on vehicle safety."

English: It looks OK, but don't blame us if something goes wrong...

Friendly advice (absent any responsibility for unexpected events): - go ahead, you'll be fine... I've done it and it has responded just as expected...

Sorry for the disclaimer - but whenever asked the question "It's totally safe, right?" - any answer should have a healthy dose of disclaimer...

There are at least 2 other posts on this topic that include further background information that you may find helpful.

 

I consider it safe, as Eric points out nothing is totally safe from a legal standpoint.

Recommend adjusting the big green thing first, it turns 90 degrees to unlock (turn the green thing with your hand not the brown thing) then move it up or down (up in your case) to adjust and then relock. You can check the adjustment by watching the brake lights. The threaded adjustment on the rod would be for a fine adjustment only and may not be needed. Mine came out just right by moving the green switch up a notch or two.

 

please provide link to instructions with pictures

 

Great post! The disengagement of the CC is my #1 gripe about the Prius. I'm going to try this and see if I can make this better.

 

Modifying one's behavior to disengage CC by way of the steering column switch is an obvious alternative to this more technical method, of course.

 

Is everybody aware that pulling back on the speed control lever disengages cruise control? No need to touch the break pedal if you just want to coast or manually control the car's speed.

 

That is true, but the adjustment also causes the brake light to come on much earlier and thus gives earlier warning to following drivers that you are hitting the brake. That is why I did the adjustment since I almost always disengage the cc with the stalk lever. I'd only disengage with the brake in an emergency.