ABS Brakes Activating?

LARRYT57

MEMBER
2013 TOYOTA PRIUS
4 CYL
2WD
AUTOMATIC
168,000 MILES

It felt like a mouse was running under my foot under my bent non-using leg then started hearing a metallic sound several miles later. I took it to the mechanic the next day and he gave me over to a young guy who said he thought it was the ABS pump (90%) and that it will be an expensive repair. He did not answer my questions in a confident manner and was not well versed on this issue, so I need to find someone else to do the repair. There is no warning or light signal, and the car and brakes are driving as usual except for the metallic sound if the brakes are depressed hard. Firstly, do I need to be afraid my brakes will just fail, I have only driven it 5 miles since the problem began? I need to drive a few miles to buy some food and will have to get to the new service garage when I find someone to do it. Is that an issue? Also is this a repair that a mechanic can do with a used part to save me money. Any help understanding this issue would be appreciated. I never had an ABS problem before. Thank you!

Friday, November 10th, 2023 AT 8:00 AM

5 Replies

KEN L

MASTER CERTIFIED MECHANIC
50,088 POSTS

If you do not have an ABS warning light on, the system is operating correctly. The problem comes when the front or rear wheel bearing hub is starting to go out allowing the ABS wheel speed sensor to misalign with the reluctor wheel on the axle which makes the ABS system activate hence the feeling and sound on the brake pedal. Can I ask if the problem occurs more when in a turn? If so, this will be a bearing hub, most likely the front. I would raise the car up and grasp each wheel to check for endplay.

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

and

https://youtu.be/_FzmmBoa4Tg?si=4yxT3JuAgkR_EQSG

Here is how the front hubs are changed out. Check out the images below. Please upload pictures or videos of the problem so we can see what's going on.

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Friday, November 10th, 2023 AT 10:38 AM

LARRYT57

MEMBER
3 POSTS

Ken, thank you so very much for your response. I live in Brooklyn, NY so repairing it myself is not possible and it is hard to get up to any speed that satisfies me. I know it's a Prius, but I like to get where I need with haste and always have prided myself on knowing how to drive. I told the mechanic that when I got it to a higher speed in the 55-70 mph on the few highways when not going bumper to bumper, the car sounded louder than at lower speed and sounded like it was coming from underneath toward the rear of the car. I do not hear anything abnormal when I make any turns and though I was driving it gingerly today I did not hear that metallic sound either. I was really going gently with it. There is definitely no warning light on the dash. Judging from your advice I am thinking it may be a rear wheel bearing hub. I began driving when I turned 14 and when my mom died at 16, I got her car even though I was not legally allowed to drive. It was my escape, so a car has always been really important to me. My father was in the wholesale auto parts business after owning a gas station and repair shop. He said he wanted to see his kids more so left the station life. Gas was then 5 gallons for $1. Again, I appreciate your considerable kindness.

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Friday, November 10th, 2023 AT 3:37 PM

KEN L

MASTER CERTIFIED MECHANIC
50,088 POSTS

I am so sorry about your mom; my father too owned a gas station and that is where I got my start. It was 28 cents per gallon at self-serve unleaded. If you can hear a noise from the rear the bearing hub can be bad, here is what the shop will need to do it fix it. Can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. You can upload it here with your response. Check out the images (below). Let us know how it goes.

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Saturday, November 11th, 2023 AT 9:52 AM

LARRYT57

MEMBER
3 POSTS

Ken, I took the car out and did everything I could to make the symptoms reoccur and now it's driving like I was dreaming it all. Can't make this crap up. I am sure it will return. Now I have the time to find a shop I can trust and establish a relationship going forward. I am a retired dentist. I am well versed in a great deal of the medical field as well. If I can ever be of help to you, it would be my pleasure to provide to you that you have done so expertly for me. Keep my email and let me know if you need any information or understanding. Thank you.

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Saturday, November 11th, 2023 AT 12:39 PM

KEN L