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Do I need to replace some components of my braking system?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Taxi/Limo, Jul 26, 2023.

  1. Taxi/Limo

    Taxi/Limo Active Member

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    Do I need to replace some of the components of my brake system
    I am getting the following codes

    Under ABS/VSC/TRAC
    C1256 Accumulator Low pressure
    C1253 Pump motor relay

    Under PM2 Gateway
    U0100 Lost communication w ECM/PCM "A"

    Under Precollision I get
    U0100 Lost communication w ECM/PCM "A"

    Also what is a PM2 Gateway?

    Thanks
     
  2. Tombukt2

    Tombukt2 Senior Member

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    ABS pump and accumulator is going out if this is a generation 2
     
  3. Tombukt2

    Tombukt2 Senior Member

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    For the generation 3 there are two components You need the isolate which one is the problem or replace them both like many seem to do.
     
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  4. Mendel Leisk

    Mendel Leisk Senior Member

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    This video is pretty good:

     
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  5. Tombukt2

    Tombukt2 Senior Member

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    This is one reason why I don't really care for the Gen 3 You notice in the Corolla Camry and other cars this is all the one piece unit mounted in the front of the car that can be accessed by the lines and three bolts generally in and out in minutes in the generation two it was bad enough being behind the inverter but at least the electronics package and the pump and accumulator which are the problems generally are all on the one unit The thing that sits on the firewall is just like an old master cylinder more or less takes a long time for them to really go bad so when you pump your foot or push on the brake pedal in the generation 2 you move fluid normally it seems like through hydraulic lines over to the accumulator and pump which then takes over and does its thing now in the generation 3 they separated the so-called booster which is your electronics package and your sensor and put the accumulator and the pump on another rack so you have to buy $1,500 worth of parts or in the generation 2 it generally was considerably less but just the other day my buddy bought the generation 2 part and it cost $1,200 even buying it online with the discount through Rick Hendrick without that it would have been almost 1700 and something not a good situation but it is what it is. This will keep me out of the generation 4 and the p h e v doodad unless I see they have rework this on the later later models like the Corolla which the things that's right up in front of the car you can buy rebuilt units online for $140 etc etc kind of like the way ABS was before people started fooling with it again. We all remember when ABS was a thing in the early '80s and every part in the system cost over $1,000 even back then then Bosch straighten that out for a long time everything got very reasonable. Then Toyota and a few others decided to make it complicated again I guess just because? I guess just because?
     
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  6. Taxi/Limo

    Taxi/Limo Active Member

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    Can a problem with the booster and accumulater cause the car to shut down and throw a U0100 code?
    Thanks for the information so far guys