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2017 Prime Brake Bleeding

Discussion in 'Prime Technical Discussion' started by PriusPostus2, Apr 23, 2023.

  1. PriusPostus2

    PriusPostus2 Member

    Joined:
    Aug 30, 2017
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    Location:
    Seattle, WA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Unfortunately, a mouse (or several meeces) chewed a small hole at the top of the plastic brake fluid canister on our 2017 Prime. I duct taped the hole until I was able to find a replacement canister.

    Side Note: Toyota only sells the canister along with the entire master cylinder control unit, MSRP $2008.76. I found a used unit for $130 and was able to swap the canisters using gunsmithing roll pin punches, and not even have to unbolt the main unit.

    I was careful to try to not let air into any of the lines, but wasn't successful. Of course codes were thrown when I started the car and the pedal is soft. Now I need to bleed the system.

    Question 1: is it possible to bleed the entire Prime brake system without a TechStream? If so, what is the procedure?

    Question 2: if I do need TechStream, will the software work with either the OBDLink EX (USB cable) or OBDLink LX (Bluetooth) that I already have? The supplied software seems to only retrieve and clear codes, not command the modules.

    Thanks!
    PriusPostus
     
    #1 PriusPostus2, Apr 23, 2023
  2. Elektroingenieur

    Elektroingenieur Senior Member

    Joined:
    Jan 8, 2017
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    3,258
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    Location:
    California
    Vehicle:
    2016 Prius
    Model:
    Three Touring
    According to Toyota, it’s not: the caution mentioned in my posting about fourth-generation Prius cars also appears in the Repair Manual (more info) for Prius Prime models. I suppose there could be some third-party diagnostic tool with equivalent capability, but I haven’t looked for one—and even if there were, I’m not sure I’d trust a reverse-engineered product with a task that’s so important to safety.
    Techstream requires a vehicle interface module that provides an SAE J2534 library; see the last pages of Toyota’s FAQ (PDF). I haven’t used OBDLink’s products, and their website doesn’t mention J2534. You could ask them, or check for yourself: on a PC with Microsoft Windows, with the OBDLink software installed, is there a registry key under HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\PassThruSupport.04.04 for their device? That location is defined (without WOW6432Node—it was a gentler time, with fewer bits) in SAE J2534-1 DEC2004, and on my computer with Techstream and MongoosePro MFC2 software, the J2534 libraries are registered there.
     
    #2 Elektroingenieur, Apr 23, 2023
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