Prius C $2,902 brake dealer job

You could try contacting Toyota corporate, see if they can do some goodwill compensation, say 50%? Dealership might be able to contact them too, more direct.

 

Sorry to hear that. Is this a common problem for 2012 Prius C?

How many miles do you have on your car?

 

Try to find a place that can rebuilt that the manifold assy. with a warranty especially where you are or even here in the states. Depending on the condition of yours but you might wanna use that core for you know the history of it. Not like an exchange, sometimes the housing are loose or out of specs.
Shouldn't cost that much to ship it. That's actually in the back of my mind too which will be a possibility to happen along the way. This company rotex, I brought in hundreds of alternators, starters, power steering, hydro boost since the 80's. That's what they do and they have been an expert since. If they cant do yours, they will guide you to he right place to get it done the right way.

 

If you look closely at that fortune cookie, it says "Abnormal Leak of ACC PRESS", and of course 'actuator' does not have two 'C's, so you know it is talking about the ACCumulator.

On the other hand, when accumulator pressure does not hold, the fluid can be escaping through paths either in the accumulator or the actuator, so the code's fortune cookie just doesn't really give you any help deciding which component has the problem. If you are a gambling sort, there are more valves inside the actuator, so that might be your first bet.

The part names trip people up all the time anyway. Which of these did you actually replace? (This illustration came from Gen 3 liftback docs, but I think the c is similar.)



The thing on top is also called the actuator. And also the master cylinder. And also the Skid ECU.

The thing on the bottom is the "accumulator" or the "booster pump". It isn't the "booster"; that's again one of the names for the thing on top.

 

So you bought the one on the bottom in the picture, that looks like two horizontal cylinders?

 

I'm not sure. There are more valves contained in the actuator (the upper part, a/k/a booster), so I might suspect that gives it more ways to go flaky. But we'll see.

 

Nitrogen is the gas used, and there was indeed a recall involving cracks in the metal bellows, for 82,000 Gen 3 liftbacks from model year 2010 in the US. Those were made with accumulators having the metal bellows slightly undersize, so that road vibrations caused the metal bellows to vibrate vertically and strike the insides of the accumulator and develop fatigue cracks, allowing the nitrogen to leak out. Those accumulators could be recognized by the position of their labels:



Now, just the fact that some tens of thousands of early accumulators had a defect, where they developed cracks early, doesn't necessarily mean that other non-undersized bellows can never develop cracks at all. Nothing is forever and even properly built things will wear out someday, so it is a possibility that can't be ruled out.

At the same time, the Gen 3 liftbacks have another, separate, ongoing concern with the brakes, campaign ZJB, where some valve in the actuator may wear and fail to seal completely, so there is a small leak of pressurized fluid from the accumulator back to the reservoir, and the accumulator cannot hold pressure. There is an open NHTSA investigation trying to find out if there is some reason those hydraulic valves are getting worn out or stuck sooner than expected.

Note that in that failure, what is 'leaking' is brake fluid, not nitrogen gas. You end up with the same observable symptom: the pump runs to fill the accumulator with fluid under pressure, but the fluid slowly leaks through a valve back to the reservoir, and the accumulator pressure drops, and the pump has to run again. But what is 'leaking' is different, and the problem is in a different component.

You also run into a lot of PriusChat posts where people mix up these two issues, which do have the word 'leak' in common, but are otherwise completely different, all the way down to what is 'leaking'.

Some of the threads where the confusion seems to be worst are put up by posters who may or may not be, but act a lot like, plaintiffs' attorneys trolling for people to join lawsuits, and they write a lot of rubbish where they either genuinely fail to grasp the difference between the two issues, or deliberately muddle them together anyway in a lawyerly effort to stick spaghetti to the wall.

 

I've always thought it likely that with a leakage rate that high, it should be pretty easy just using a mechanic's stethoscope to pin down where that leak is. I haven't had a chance to try it though.

In the absence of a problem, you get very bored waiting to see that pressure leak down.

Right. The names are confusing because each assembly has multiple things in it, and even the Toyota literature can call them by different names. The thing on the bottom with two cylinders has the "booster pump" and the "accumulator" and it can be called both of those things, but not the "booster" (that's in the thing on top).

The thing on top has the "master cylinder" and "booster" and "actuator" and "skid ECU" and can be called any of those things depending on where you are in the manual, but again the "booster" is not the "booster pump" (which is in the bottom thing). And the "actuator" and "accumulator" are easy to confuse because of the ac-, but one is in the top thing and the other isn't.

Every time I write all that I tend to hear Bud Abbott in my head saying "oh, that's our shortstop."

 

That’s interesting.

With mine (assuming it’s normal), if I raise hood first thing in the morning, level is high. Open drivers door to trigger pump, level drops, and stays down.

It must be gradually climbing back up, but not over the 10~15 minutes I watched.

 

Sounds like yours is holding the way it's supposed to.

 

Yeah knock on wood; it makes the occasional sound. Dealership mentioned a software tweak, which I believe you’ve had done??

I brought it in for them to hear, check it over. They charged $80~ for that inspection, told me all ok, but they could do the software update, but that would be extra.

Worthwhile?

(Appreciate I’m hijacking thread, sorry.)​

 

I didn't like the honk, so I paid them ~ an hour of shop time to flash the update, and it made me happy.

Worthwhile?