Brake accumulator, and brake bleed. Has an Interesting result.

my 2009 prius is showing the exact same issue and exact same sounds as I hear in the video i.e. the gears continuously cycling in the accumulator and the high pitched turkey noise. Did this get resolved completely after replacing the accumulator or was there an air leak somewhere else? My prius also worked find for a few days after the mechanic flushed the brake fluid, then again the noises and ABS/VSC checklights reappeared. I will really appreciate the response!

 

As you can see from discussion earlier in the thread, there's an "accumulator" in the system that's filled with high-pressure nitrogen gas. If that gets old and leaky, some nitrogen can end up in the brake fluid, and then that comes out as bubbles when you do a bleed, and you wonder how some air got in. It would have been pretty strange for outside air to leak into a system that's pressurized. But the nitrogen that's already in there, under pressure, that's another story.

 

ok cool, thanks for the explanation. Did you have the same exact issue happening in your Prius or slightly different? Mine has the same exact issue like the OP kens97uber171. So did this issue get fixed completely in your car after you changed the accumulator?

 

I don't have a Gen 2 personally and haven't had to deal with that issue personally. But the system in Gen 2 makes things pretty simple: because the actuator, pump, and accumulator are all in the same single assembly, if you're having that issue, there's not much mystery what to replace.

 

Do you know if the accumulator used on toyotas use bellow accumlators across the lineup or just on the hybrids? I'm considering getting a standalone accumlator from a highlander>

 

What else are you thinking they might use?

 

There's other types of accumulators out there that uses a bag instead of metal bellow but im not sure if its used in a an automotive setting. But im pretty sure toyota uses all metal bellows.

 

That's what I think too.

 

I'm going to have to bite the nail and do some experiments on the ABS modules. 1. The communtator wears out and needs a remedy. 2. finding the right carbon brushes. 3. Using accumulators from other vehicles. 4. converting DC motors from another make into the two prong connectors.

 

Out of curiosity do you have any opinion on the following ?
ABS light suddenly came on and I noticed a telltale sign of fluid on the rear right wheel. Next morning all the fluid had drained out of the reservoir from that wheel which told me the pump had been operating to pump that much fluid out.
Replaced brake cylinder and started to do a bleed without Techstream so I could drive it to the shop. Heard actuator motor running but no fluid was coming out of the bleeder on that rear right wheel.

I replaced