2015 Gen 3 brake pump failure?

I would imagine that if there is a leak of some type, there should be some residue somewhere. I'm not familiar with the 2015 Prius braking system, but if a there is a loss of pressure, either their is air getting in the line or fluid is leaking out somewhere. Hope this is somewhat helpful.
I have 78k on my 2015 and have not had any brake pump issues.

 

Brake booster failure is common in gen3. The pump builds and accumulates hydraulic pressure for the braking system, allowing for brake by wire 100 percent of the time. The master cylinder is very complex and includes a lot of valving and solenoids necessary for ABS, Regen, traction control and other functions. Sometimes a loss of hydraulic pressure occurs in the pump or in the master cylinder between flowpaths, not necessarily to the outside world. It is a flawed design that Toyota replaces for free over 10 years or 150k miles on most gen3s.

They replace both the pump and the master cylinder, which is probably or hopefully what your dealer is suggesting. You are getting a good price if both parts are being replaced without a code yet.

With that said, dealers generally do not replace anything until it creates a code. Most the time the system is really bad when the pump is cycling every 30 to 60 seconds or faster at a stop sign or when in Ready and in Park.

So you may not be at the most critical point yet with codes - although if work is done, they should be replacing the master cylinder and pump. No code means you pay. Often dealers don't tell you about the programs because they make far less when Toyota is paying.

 

Many people on here have waited till the noise happens as often as once every three minutes before doing the repair....

 

Unless there's something more you're not telling us, everything you just said—a run when opening the driver's door first thing, and a run when you use the brakes but not every time—is pretty darned normal. Had it recently changed in some way that made you want to ask?

If it starts pumping every time you brake, or, worse, pumps by itself repetitively when you're not touching the brake, that's when some kind of issue is indicated. (Often, as rjparker indicated, it will be an internal leak, where fluid just makes its way back to the fluid reservoir; nothing is 'leaking' out of the car.)

 

3 seconds? mine whines for 10 when i open the door

 

Yep, same here. Sounds like a sheep.

 

That because people whine/wine alot in your family... Your Prius has for too long been trying to feel loved and accepted into your family. Of course ever since you turned down the Nexcell opportunity for her she's looking for any possible opportunity to end the relationship.

 

Toyota corporate won't pay without a code. So pressuring the dealer won't help even though they may admit the system is weak.

The most common code is a failure to reach pressure over several minutes. At that point the dash will light up like a Christmas tree. You may be years from that or perhaps it will fail sooner.

There is a reduced braking force failsafe but drivers have a hard brake with increased stopping distance, worse case. I have not heard of anyone who lost their brakes completely but many have experienced bad or failing brake booster systems.

A Techstream brake flush may help at this point. In my more advanced 15 second cycling case, a Techstream flush cleared up the rapid cycling for a couple of days.

Toyota's customer support program is ten years or 150,000 miles. It is likely yours will be up in late 2024 to 2025 based on date of purchase. Unless 150k miles are exceeded before then.

 

Can you tell us more about being a "safety addict." That seems like a bit of a disability... I mean in the name of safety I probably wouldn't get off the coach very often?

 

I just changed my 2013 Prius pump/accumulator combo. When I first decided I had a problem it was running for about 1.5 seconds every 18 seconds. As miles added up it got down to only 13 seconds 'between pumps'. Nearby Toyota parts man said the most often failure was the master cylinder, so I got one online for $711 plus tax. As I was removing the old master cylinder I thought, "maybe the pump/accum. is faulty", so I ordered that online for $450 plus tax. It turns out the master cylinder is good because after replacing only the pump/accum. my brakes work FINE ! Hallelujah ! I returned the master cyl. yesterday. When I talk with the Toyota service mgr who told me I did not have a problem because there was no code [at 200,000 miles] I'll ask him if he thinks maybe I'll visit the Honda dealer when it's time to buy a newer hybrid. Maybe they will be more helpful. I got help from this website and from U-tube.

 

Bleeding the system was a piece of cake with my wife of 57 years pumping the pedal --- just like any of the 23 previous used cars I have owned during my long & happy life. There is a bleeder port on top of the master cylinder which we bled first, then I did right rear, left rear, right front & left front, in that order. Maybe because I merely put the old master cylinder back into the car i did not need any special scan tools at a cost of $250.00 plus tax.?