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

2017 Prime Brake Bleeding

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

  1. PriusPostus2

    PriusPostus2 Member

    Joined:
    Aug 30, 2017
    54
    83
    0
    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
    2,515
    3,268
    9
    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
(You must log in or sign up to post here.)