ABS ACCUMULATOR?

2013 TOYOTA PRIUS
136,000 MILES • 4 CYL • 2WD • AUTOMATIC
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BHAMDOC1973
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Common issue with these cars and other Toyotas is the abs pump which throws all the lights on the dash, I usually pressure the whole assembly, the accumulator and the booster pump or whatever you call it, which is higher in price, but not knowing which is the issue is what am having a problem with. When the code says low pressure in accumulated, which part is it the 1st or 2nd picture?I usually buy them both as a unit so its less headache in case the other one is what is causing the problem
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Sep 20, 2025 at 9:32 AM
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STRAILER
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The accumulator is under extremally high pressure so I wouldn't mess with it. I would replace it as a unit. The accumulator is the second part of the picture.
Sep 21, 2025 at 8:57 AM
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BHAMDOC1973
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Right but what am asking is, when these codes pop up is it usually the accumulator that can be bad alone or does it need to be both the accumulator and the booster assembly? I do not intend in playing with the accumulator but actually replace it. I usually replace both but buying both is so expensive, that is why I want to replace just the accumulator assembly
Sep 28, 2025 at 2:02 PM
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STRAILER
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What codes did you get? I would try to get a used unit from ebay I have had good luck with there parts.
Sep 29, 2025 at 9:26 AM
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BHAMDOC1973
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c1391
Sep 29, 2025 at 11:19 AM
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STRAILER
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Yep, that is an accumulator code aright, pretty straight forward.

C1391 - Abnormal Leak of Accumulator Pressure

I would replace the unit as a whole piece.
Sep 29, 2025 at 4:31 PM
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BHAMDOC1973
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Ya I ordered one, hopefully it will solve it, what in the heck does happen to these? why do they always go bad? seen it on Prius, Lexus, rx and more, just weird, and then people say they are reliable, never been a Toyota fan
Sep 29, 2025 at 4:46 PM
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STRAILER
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Yep, what happens it he bladder inside of the accumulator ruptured and looses pressure inside the brake fluid. So they need to be replaced. All cars have problem, this is one of Toyotas :/ Let me know what happens.
Sep 30, 2025 at 9:09 AM
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BHAMDOC1973
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I replaced it and did the bleeding procedure twice using the scanner but there is some bubbles coming from the reservoir and a hissing sound, there is no brake fluid leak anywhere so the used one must be bad. I never did have that hiss before, and since the accumulator keeps cycling on and off while parked and off it took down the 12v battery over night
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Oct 8, 2025 at 12:52 PM
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STRAILER
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Wow, that sounds bad, is it a used unit? If so I think you got a bad one. Also, did you use a scanner to open the ABS valves when bleeding? If the system is bled but still makes that noise I would get another ABS unit, thanks for the videos they help.
Oct 9, 2025 at 10:01 AM
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BHAMDOC1973
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Yes, I let the brake system just like I always do using the Adel scanner. I'll have to open each valve more than once lick the stroker and everything else it does it on his own. All I have to do is open the valves and closing.
Oct 9, 2025 at 10:25 AM
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STRAILER
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If it is bled and it makes that noise the unit is no good and you will need another, it is used correct?
Oct 10, 2025 at 8:23 AM
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BHAMDOC1973
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Yes
Oct 10, 2025 at 8:42 AM
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STRAILER
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Sorry about that, I would replace the unit again.
Oct 11, 2025 at 9:06 AM