ABS pump making noise

Any warning lights or diagnostic codes set? By fluid level varying you mean the brake fluid reservoir level visibly changes from full to one-half full? Can you describe what you hear or see while it does that?

 

Been there done that. You need a new pump or master cylinder or both.... preferably both......
I bought them used online out of a Lexus..... supposedly 50,000 miles $210.00
I changed them myself...... not a easy job...... or you can take it somewhere and get new installed but probably $2000 or more....

 

Classic Accumulator, Master Cylinder symptoms.... same thing mine did.

 

Agree, except for the varying reservoir levels.

 

Changing reservoir levels is exactly how the system normally operates ... only slowly!

When the pump runs, it pulls fluid out of the reservoir and forces it into the pressure accumulator. The reservoir level goes down.

In a normally functioning system, the reservoir level only goes back up gradually, as you use the brakes, and fluid returns to the reservoir. Or very slowly, say overnight while the car is parked, most of the fluid from the pressure can might slowly return to the reservoir, which is why the pump often runs when you open the car first thing in the morning. Or if in Techstream you request a "zero down", all the fluid from the pressure can will be immediately returned to the reservoir and the level goes back up. (The level marks on the reservoir are placed for when the system is zeroed down; if you ever check your fluid level when the pump has recently run and you forget to zero down, it will look lower than it is.)

If yours is returning fluid to the reservoir so fast you can watch the level rise, and then seconds later the pump has to run again and make the level drop, there is an internal leak in there the size of Niagara.

 

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I agree that a fast varying level suggests accumulator leakage, but the brake reservoir fluid level on our v Five does not vary at all.

 

I could watch mine going up and down before I changed the parts.....

 

We must have a very tight accumulator. Not complaining!

 

I got the brake letter from Toyota today.
I will post it when I get home.

 

Coincidentally, we also got this letter today. No manifestation of issues, so far, thankfully.

 

Hello. I know this thread is a bit old. But I was wondering if someone can post the letter in its entirety? I am interested to know how long the extension was and if we can still take advantage of it as we are now experiencing these issues. Thank you.

 

Hi..... Do you have any extra lights on the dash.... malfunction. Or just the pumps running

 

How many miles on your 2012?

 

192k Miles. The pump runs constantly and has a weird noise now when pressing the brake pedal. I see on the TSB it says Dec 31, 2021 regardless of miles. So I hope it is still covered. Currently no lights on the dash. Thanks.

 

I spoke too soon. Lights on the dash just came on. The brake light, the ABS light, and the traction control light.