I bought my 2008 Prius used about 7 months ago. Currently, it has about 125,000 miles on it. The car makes a periodic sound like this. (The video is not mine.) Recently it has gotten more frequent (sometimes it makes this noise even after the car is turned off). So I took it to a mechanic and he said my ABS module is failing. He also suggested that I should replace it as soon as possible. However, I never had any error code (ABS, VSC or traction) come on. I have 3 questions: - Should I be worried about the ABS module and change it right away or wait till the lights come on? - I know it will be an expensive fix and I am questioning whether it will be worth it to change the ABS module. I was planning to drive it for at least 100k miles more before getting a new car. -Should I order the parts on eBay? They seem to be much cheaper. But I am afraid the used parts may have the same faults as this one and will go out quickly.
Many report trouble lights only come on at system failure (no power brakes/ABS). Car is still driveable but not safe. Then, yes you will need to attend to this matter. You'll also need to budget for other big ticket items too. Valid concerns for most used part purchases. GOOD LUCK!
Brake hydraulic circuit uses an accumulator pump. That noise may be normal. Even when the car is off, 12v battery is used to precharge the accumulator once in a while. Same thing happens when driving, even when you may not be using the brakes.
My 2011 grayghost just fixing to cross 200K and started increasingly turning on that eeeeeeeh noise about every 10 sec. I started hearing air leaky noise in cabin...at brake pedal...upon further inspection I pulled boot back and felt moisture too...hummm brake fluid! .Soon after thru a Christmas tree of lights on dash... shutting off all safety features of braking ...slowed up regenerative process too.. engine still charged traction bat. She still drives but with ol school brakes no modulation. Gonna pull codes tomorrow... then diagnose... hopefully be able to pull any needed parts off my parts Prius...It was working awesomely till bumper cruncher with pickup trucks rear bumper...00000uch
Because your car is a 2011 which makes it a Gen 3 and because the Gen 2 (the cars in this forum) and Gen 3 are different in this area, you should really post your question in a Gen 3 forum. You will get much better advice specific to your generation of Prius.
