Abs brake system

We recently had new rear brakes and new rear rotors put on our 2000 Lexus 300rX. We’ve been back to the repair garage twice because of the noise the brakes are making. We have been told they are safe, but the first time they told us they were making noise because they hadn’t adjusted in yet. The second time they said it was because the pressure in one of our tires was low and it was causing the ABS brakes to kick in. We went to a tire dealer to have the tires and rim checked and they said they are fine and their is no truth to this being the cause of the problem. Does anyone know why the ABS system is kicking in? Could they have used the wrong brake pads.

What kind of noises is it making?
If the ABS system were kicking in, you’d feel the brake pedal react and pulsate, the noise you’d hear would be a grinding or popping but it’d be at your foot, not at the rear.

This is probably not an ABS related thing but please describe the noise, as well as anything else related, and we can figure out what this is.

-Matt

You should be able to easily tell if the ABS is coming on as suggested above. You should feel it in the brake pedal. If you are not sure what it feels like drive over some railroad tracks and brake fairly hard. Do it safely with no none behind you.
You could remove the fuse for the ABS to disable it. Then go for a test ride and see if the noise is still present. The dashboard Light for the ABS will come on. It should go off when you reinstall the fuse.

This does sound a bit far fetched especially. You need more information but I would bet they used inferior (Cheaper) pads that don’t have sims to dampen vibrations. Also, If they turned(resurfaced) the rotors versus replacing them, they may have given them a poor surface finish.

There are things that can be done to eliminate the noise and it is disappointing they would not do them for you.

It is just annoying to have a noise on a high end car that I am sure you paid good money for. I would be leary of using this shop again.