1. Attachments are working again! Check out this thread for more details and to report any other bugs.

How to remove a brake caliper???

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Bronze84, Mar 24, 2014.

  1. Bronze84

    Bronze84 Member

    Joined:
    Nov 21, 2012
    118
    25
    0
    Location:
    South Derbyshire
    Vehicle:
    2008 Prius
    Model:
    N/A
    Hi guys.

    One of the pistons in my driver side (UK) front brake caliper is sticking, so I've bought a second hand caliper just to fix the problem until I come to sell my pri in a month or so.

    Is it a case of old one off, new one on? Or is it not as simple as that? I've had a go at most things on cars over the years but have never needed to replace a caliper?

    Cheers

    Martin
     
  2. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Hi Martin.
    The changing of the caliper is is the easy part. From memory disconnect the 12 volt battery, plus two bolts and one hose to undo. Bleeding the system afterwards is the harder part.
    If you have the Mini VCI the brakes are relatively easy to bleed following the instructions in the Techstream program, without it is very difficult. There are instructions here on PC, but the search facility being what it is they are not easy to find. If I can find the link I will post it. In the mean time let us know if you have the VCI.

    John (Britprius)
     
  3. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    usnavystgc likes this.
  4. Bronze84

    Bronze84 Member

    Joined:
    Nov 21, 2012
    118
    25
    0
    Location:
    South Derbyshire
    Vehicle:
    2008 Prius
    Model:
    N/A
    As always John, most grateful for your help. Looks like I'll be doing it the old fashioned way :/
     
  5. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Be sure to disconnect the battery before you start. If the pump starts up while you have your fingers in there you could loose one.

    John (Britprius)
     
  6. Bronze84

    Bronze84 Member

    Joined:
    Nov 21, 2012
    118
    25
    0
    Location:
    South Derbyshire
    Vehicle:
    2008 Prius
    Model:
    N/A
    Will do. I've got scanner if any fault codes should show. Like you say, it's the fluid bleeding bit that concerns me
     
  7. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Does the scanner show brake codes for the Prius? As a lot of the scanners only read emissions relate DTC's.
    For the costs involved if you have a laptop "preferably an older one with Vista or XP" I would buy a VCI for around £20. You could always sell it on afterwards perhaps to a member on PC.
    If you lived closer you could have borrowed mine.

    John (Britprius)
     
  8. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Just had a thought, you are sure it is the piston that is sticking? There is only one piston on the Prius front caliper, and often if one pad is warring more than another it is the slide pins sticking that is most often the problem. These can be replaced or cleaned, and lubricated without needing to disturb the hydraulics.

    John (Britprius)
     
    dorunron likes this.
  9. Bronze84

    Bronze84 Member

    Joined:
    Nov 21, 2012
    118
    25
    0
    Location:
    South Derbyshire
    Vehicle:
    2008 Prius
    Model:
    N/A
    Well I'm presuming that it is the piston sticking as there is an awful squealing noise as low speed (up to c.30mph) which won't go away, I only have to touch the brakes in slow moving traffic for it to start squealing, which makes me think it's the piston

    What does the slide pin look like?
     
  10. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Have you checked the pad thickness inner and outer as the is a warning device on the pads that makes a squealing noise when the pads are at the 1 mm ware limit.
    Seized caliper pistons do not normally make a noise. They will increase fuel consumption, and will get the brake disc hotter on the side that is sticking. I do not say it is impossible you have a seized caliper, but I am not at all convinced this is tour problem. Jacking up the front of the car "both sides" and turning each front wheel by hand will soon tell if one brake is sticking.

    John (Britprius)
     
  11. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    [​IMG]

    The slide pins are the ones seen in the above picture. The very bottom of the picture to the left of the pads and shims you will see a small rubber bellows with an out of focus nut at the end where the caliper bolts on, "the caliper has been rotated upwards on the top slide pin just off the top of the picture". That nut is part of the slide pin, it should be free to rotate "once the caliper is unbolted from it as in the picture", and slide in and out of the casting at the other end of the bellows, movement restricted only by the rubber bellows.

    John (Britprius)
     
  12. whburling

    whburling Junior Member

    Joined:
    Sep 10, 2006
    53
    17
    0
    Location:
    Gales Ferry, Ct
    Vehicle:
    2006 Prius
    Model:
    II
    John,

    What worries me is that I believe my prius 2006 (generation II) has pressurized brake lines. So....I am imagining that if i disconnect my caliper from the brake lines....the brake fluid will drain under pressure. I am not sure, but I suspect my generation two has an accumulator which may not be able to keep the pressure up.... resulting in the creation of an error that will have to be dealt with as well.

    I just purchased a mini vci or whatever that device is called and i downloaded the latest techstream software but have not yet tried the two together.

    I was hoping to find a YouTube video detailing brake caliper removal and brake fluid replacement. I did find a wonderful explanation for a generation III Prius (by HTS Autoworks discussing the details with a Toyota Aqua Prius C) but i vaguely remember that there is a difference between generation 1 and 2 (one had an accumulator and two did not???) and generations 2 and 3 (not sure what the differences are.
    So i am in a bit of a quandry as to what to expect.

    I value your insights. I have followed your recommendations over the years. I am not a mechanic so if I state something that is not true, then please correct me.
     
  13. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    The gen2 (2006) does have a brake accumulator, and electrically operated hydraulic pressure pump. This pump can start at any time even with the car turned off and the key fob well away from the car. This does pressurize the brake lines. Opening the drivers door is a sure way to start the pump.
    The easiest way to change a front caliper is to fit a hose clamp to the caliper flexible hose "cutting off the supply of fluid to that caliper". Then remove the caliper.
    Before starting work you should disconnect the 12 volt battery. Toyota says you should also remove the 2 light blue relays in the fuse box under the hood.
    Bleeding the brakes after the work is complete requires the VCI with Techstream, and 2 people. There is a walk through in Techstream that guides you through the process.
    I hope this helps. The job is not as difficult as it sounds, but following the correct procedure is important. Any codes that do appear can soon be removed with the VCI.

    John
     
  14. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Disconnecting the 12 volt will effectively prevent the pump activating, anyway.
     
  15. whburling

    whburling Junior Member

    Joined:
    Sep 10, 2006
    53
    17
    0
    Location:
    Gales Ferry, Ct
    Vehicle:
    2006 Prius
    Model:
    II

    Afternoon, John

    God How I value your comments. practical yet with consideration of Toyota advice.

    I purchased a VCI with Techstream. I received both. I was given a password to unzip the software, but was stopped cold when I came to the SB 822-01 Configuration step. It asked for my dealer name, dealer code, dealer phone, country, and user type. Except for the last two questions, i have no idea what to enter for data and have Techstream continue to the state where i can use it. Please advise as to what to do.
     
  16. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    What version of Windows are you trying to load Techstream? If it is Windows 7, 8,or 10 64 bit go hear for loading information.
    Techstream TIS VCI Installation Guide (64-bit OS) Including All Software Needed! - Scion FR-S Forum | Subaru BRZ Forum | Toyota 86 GT 86 Forum | AS1 Forum - FT86CLUB
    If you are useing Windows XP 32 bit, or some earlier windows system. Techstream is asking for those details the TIS KEY section of the installation is not complete. Try running that section of the disk again. Many people have difficulty loading the software the first time. If you opened Techstream before the drivers ect were installed this also causes the problem. This will require removing the program in Control Panel " Programs and features" then re loading without opening it.
    Once loaded it will ask some of the details of the car such as with or without SKS. There will also be a box at first time loading for your name, and company name, but not a dealer code. This is purely to give your details on any printout you do. Anything can be entered in those spaces.
    If this does not help come back to me,

    John