Some questions have come in regarding the Toyota Prius and brake problems affiliated with it. So we’ve taken the time to compose a quick FAQ to hopefully alleviate some of your brake servicing confusion.
1. How long can the brake pads last?
It is not uncommon to find a Prius with 70,000- or 100,000-miles with the original set of pads. This is due to regenerative braking creating the majority of braking force. But, this does not mean that other components, like hardware and rubber seals/boots, can’t fail sooner.
2. A customer brought in a Prius with brake pedal pulsation and the ABS MIL light is on, are the connected? Is it the way the person is driving the vehicle?
Rotors that have excessive runout or thickness variation can cause hydraulic pulsations in the brake circuit. These irregularities can cause the pressure sensor to trigger trouble codes C1341 thru C1344 that indicate a hydraulic circuit malfunction.
3. Can I push back the caliper piston without a scan tool?
Gently push in the caliper piston only enough to fit over the new pads and shims. Toyota says that it is not necessary to crack the bleeders during this procedure and doing so could cause more problems than it solves. If you feel comfortable blocking the brake hose and cracking the bleeders to remove displaced brake fluid, it can be done this way. See TSB BR0012 for more information. With the car still powered down with the key out of the ignition, stroke the pedal several times to bring the pads in contact with the rotor.
4. How do I deactivate the system?
If you are replacing calipers or other hydraulic components, you will have to deactivate the system with a scan tool. Most scan tools will walk you through the process that involves removing the two ABS pump relays and pumping the pedal in a sequence to depressurize the system.