2012 Prius Brake Light Always ON After ABS Motor Replacement

Background:
Prius 2012, 175K miles. East coast.
I recently replaced the ABS pump/motor assembly on my 2012 Prius (Gen 3), and now I’m dealing with an issue where the brake lights stay ON constantly, even when the pedal is released. The car enters READY mode without pressing the brake pedal, just by hitting the Start button. I noticed this as I wanted to do the brake bleeding procedure using TechStream. But Techstream does not let me access that menu as the car does not go in IGN-ON mode. It assumes that I press the brake switch before pressing the start button.

There is no leak in break fluid, ABS light is gone, the ABS motor is new and good as it does not come back again and again. Brake bleeding is pending.

Problem:
Any way, I am trying to solve this issue that the brake switch and the metal tab gap (about 1 inch, visible).
The pedal arm has a flat metal tab, but no hole for a grommet-style stopper.
Maybe a snap-on type rubber stopper that can fill the 1-inch gap? It might it have fell off?

I do not have access to another Gen 3 Prius to see if I am missing any hardware, like a rubber snap-on?

Thanks
Prakash

 

BTW, I can press the switch manually and the brake light goes off. The brake paddle seems in the normal position and feels. Though not driven and felt. I have just disconnected the battery as It will drain with the brake light on, the whole night.

There is one post I found on other form that has a picture for the 2014 Prius. It seems the metal switch plate and switch have no rubber snap-on in between.

https://www.toyotanation.com/threads/brake-light-switch-brake-lights-stuck-on.1728197/
https://www.toyotanation.com/attachments/prius2014brakeswitch-jpg.402969/
(The above are not my pictures.)

So, more likely the Master cylinder is not releasing the brakes loose enough? Should I just drive a little when the Brake bleeding still pending? Just to see if the ABS system kicks in and release brake pedal, I am still not certain if the ABS is holding on to the pedal, but without driving at least a quarter mile, how do I know that?

 

<<Are you CERTAIN the adjustment is correct. From what others have said, if it's not installed
correctly, the switch will be out of adjustment.>>

What do you mean by adjustments is correct?
I removed the master cylinder, which has 4 nuts to hold it from the inside. Then the clevis (kind of yoke) attaches to the brake pedal. The brake pedal has 2 holes. One closer to the ground and one up. The clevis would reach to the lower hole only. I attached the pin, installed the cotter pin, and reloaded the spring. Just in reverse order of removal.

Thanks for the reply.

 

<< From what others have said, if it's not installed correctly, the switch will be out of adjustment.>>
Can you direct me to a post that describes this? Thanks.

Do you mean the ABS master cylinder, installed under the hood, incorrectly? It sits in tightly with 4 nuts holding from inside of the car. It has 5 inlets/outlets and 2 hoses coming out from break fluid reservoir. All connected normally. The car showed no errors.
Thanks.

 

Correction. Not 1 inch gap between the brake pedal switch and metal switch plate, but just 1/2 inch gap.
I checked with my friend's 2014 Prius C. I checked the gap between the floor and the released brake pedal. It is 3 inch gap.
The 2012 Prius, having this issue, also has an exactly 3-inch gap from the floor in the released position.

So the Master cylinder holding back the brake pedal is extremely less likely.

 

<<M/C has been replaced and then the brake switch position seems to be off, is always to double, maybe even triple, check the mounting of the M/C to the firewall. Was there an old gasket left behind, for example, with a new gasket then added over it? Or some foreign matter between the mounting surfaces?>>

M/C was not replaced. But removed in order to replace the break/actuator assembly. The gasket was old and it stayed glued on firewall side. The M/C is pushed against the firewall flat. If anything is in between, then the 4 screws will be uneven on two sides. But all 4 screws and 4 nuts fits nice. I checked before and after photos. Now, putting the M/C back was a pain. Too tight spaces and 5 metal tubes. once M/C was wiggled in, and 4 nuts aligned with holes, it fit fine.

<<And then, of course, checking the pushrod adjustment and confirming the returned pedal height from the floor is correct.>>
Pushrod was not touched/rotated. Just removed the M/C and put it back as it is. Return pedal height from floor is 3 inch. Same as in good prius C 2014. But 1/4 inch +/- can make 1/2 inch difference between the break switch and metal tab.

<<I always advise against going straight to the brake switch adjustment, because there's just no good-enough reason for assuming it became un-adjusted simply because the M/C got replaced.>>
I agree with this.

<<But then, there was a thread here, not long ago, where it turned out the bracket holding the brake switch had gotten bent in the process of replacing things. So something like that could be worth checking.>>
Do you have link? It is possible as after the pushrod is removed and the spring is released, the brake pedal can push the switch and bracket further back.

I am also suspecting the M/C air trap may stop the pedal from retracting 1/4 inch short, that is resulting in 1/2 inch gap between switch and metal tab.