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

Brake system failure after changing front pads

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by sclieu, May 25, 2011.

  1. sclieu

    sclieu Junior Member

    Joined:
    Jul 10, 2009
    24
    3
    3
    Location:
    California
    Vehicle:
    2004 Prius
    Model:
    II
    2004 prius.

    I change the brakes on various cars all the time, and never had this problem.

    After I changed both sides, I started the car, and saw 4 lights:
    - Red brake light
    - The yellow exclamation light
    - ABS light
    - VSC light

    The car now stops funny, and reading the service manual, it says that if there's a failure detected, that it will revert back to very basic braking (no abs, only fronts, etc..)... As I was exiting off the fwy, I realized this when one of my front wheels locked up, even and I was not stopping very well. Scared the crap out of me.

    In any case, I can't see what I may have done which would cause a failure. The only thing I could think of is to bleed the brakes again, but I did this and think it's ok. Is there anything else I can check or is this something I have to get serviced? Anyone else ever see this? I saw another thread where they suspected the actuator, but it is somewhat a coincidence that it would go bad after I replace the pads? I'm not sure how the regenerative brakes works on a prius, and whether there's anything I could visually inspect to see if I bumped something???

    Any help would greatly be appreciated.


    Thx.
     
  2. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,912
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    If you bled the brakes in the normal way this is your problem. The brakes must be bled with the Toyota techstream (or equivellent) programmer to open valves in the system. I am afraid a trip to your dealer is in order. It is not required or advisable to bleed the brakes when changing pads.
     
  3. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    About all that you can do is try to reset the codes. There is a procedure here if you search for it that involves jumpering pins in the OBD connector, turning on the car, and pumping the brake 8 times in 5 seconds. If that doesn't work, you will need to see someone with a Techstream or other factory level scan tool that can properly step you through the brake bleeding procedure. The Prius is very picky about having pistons compressed or brakes bled with the ABS relays installed, and it is important for anyone doing this to read up on the procedure.
     
  4. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,073
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    How did you bleed the brakes? They don't work like normal brakes, but instead need the Techstream to properly sequence the valves. A few people have posted about changing brakes without the Techstream, but they were very careful about not introducing air into the system.

    Tom
     
  5. richard schumacher

    richard schumacher shortbus driver

    Joined:
    Mar 27, 2004
    7,663
    1,038
    0
    Location:
    United States
    Vehicle:
    2004 Prius
    Model:
    N/A
    Get thee to a dealer, dude, or risk death. And then buy Bentley's or another repair manual. (You *do* already have the Owner's Manual, right? It also is full of stuff you need to know.)
     
  6. Troyroy

    Troyroy Member

    Joined:
    Sep 23, 2010
    373
    30
    0
    Location:
    Troy, NY
    Vehicle:
    2012 Prius
    Model:
    Two
    I also have changed pads & rotors on other cars for years. I have never had to open the valve on the caliper, only pushed the caliper piston back into place.
    Is it not possible to do this on the Prius brake system. ???
     
  7. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,795
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Maybe you will want to get into the Toyota Techstream business assuming you own a laptop.
    All you need is a VCI dongle that allows your laptop to talk to the OBDII connector available on eBay & and the Techstream software is avail on the intertubes for free.

    On ebay just search "Toyota Techstream VCI".

    Good Luck!
     
  8. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    First disable the ABS, then pull the caliper and compress the piston for new pads/rotor.
     
    1 person likes this.
  9. sclieu

    sclieu Junior Member

    Joined:
    Jul 10, 2009
    24
    3
    3
    Location:
    California
    Vehicle:
    2004 Prius
    Model:
    II
    Damn it! The dealer near me charges $359 to bleed the friggin brakes! That is ridiculous!!

    I might as well invest in that Toyota Techstream.

    Does anyone know if the mini VCI techstream can bleed the brakes, and if so, has anyone done it before?

    I did some searching on this forum and am a bit confused. Some post says that it's around $500 + $55 for a 2 day subscription to the software. edthefox5 mentioned that I can just get the techstream VCI on ebay and can get the software for free on internet.

    Is that dongle-looking thing the only thing I need, except for the software (and laptop)? If I'm understanding correctly, can this be done for about $100???

    Ebay sells something called mini VCI for Toyota TIS Techstream V5.0.0.028 for under $100. Is that it? What's the difference between mini VCI and VCI?

    If anyone is willing to help me, I can certainly make it available for anyone in driving distance of LA/Orange County.

    My other option is to trade in my 2004 for a newer Prius (2009 or 2010). My reasons for trading:
    1) Almost 200k
    2) Will cost roughly $400 for new tires that are desparately needed
    3) Will cost another $350 to fix stupid brakes
    4) Car shocks are wearing out
    5) Wife (with Rheumatoid Arthritis) has difficulties getting in and out of the car because it's lower than normal, and has cloth seats which is difficult to slide into position.
    6) I had a previous engine code indicating the cat coverter is failing. It fortunately went away, but I'm thinking it's on it's last leg. Replacing this in CA will costs roughly $2k!!!

    If I do get the Techstream tool, I will probably keep the car for another year (or less), and I hope the same tool will work on the newer prius too.

    anyone have thoughts/suggestions/info on the techstream and how to use it to bleed the brakes?

    Thx!

    BTW, I do have the service manual (the hard cover one), and I did not see where it says NOT to bleed the brakes. It just says that it may cause some warnings lights to occur, or something like that. It definitely was not clear that you SHOULD not do it....

    never thought it would be so difficult.... wish I had done the homework before hand, but I thought I had previously replaced the brakes so did not even bother to look at the manual prior to doing it anyways.
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I've got a coupon from Open Road Toyota in Port Moody, just came in the flyer mail. It lists a number of services, and one is brake fluid flush, for which they ask something less $100CAN, maybe $79? It's not Prius specific, just Toyota vehicles. It could be when you show up with a Prius it turns out to be an exception, not sure, ie: Prius requires special treatment.
     
  11. FreydNot

    FreydNot Member

    Joined:
    Dec 16, 2010
    210
    37
    0
    Location:
    Seattle, WA USA
    Vehicle:
    2008 Prius
    Model:
    N/A
    I assumed he was implying you could find a pirate copy of the software on the internet.
     
  12. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    I agree, that price is a little steep, but it would take at least 2 hours, and they may have to do it more than once.

    Regarding Techstream software, I do believe, but I have not confirmed, that you can download the software with the 3 day TIS Pro subscription for $55. I have heard that "free" downloads contain viruses. The VCI tool itself looks like a Chinese knockoff of the DrewTech Mongoose. The Tactrix Openport is purported to work with Techstream, but it costs about $200.
     
  13. brick

    brick Active Member

    Joined:
    Dec 10, 2006
    1,083
    78
    0
    Location:
    Upstate NY
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Huh. I never realized that a $55 two-day subscription to TIS was an option. If that plus a $200 dongle actually lets you do things that we all think of as "dealer-only" then maybe a DIY brake job is possible? It still annoys me that this is necessary at all, but we're talking relatively infrequent stuff and it would beat the stealer. Sounds like a good research project.
     
  14. richard schumacher

    richard schumacher shortbus driver

    Joined:
    Mar 27, 2004
    7,663
    1,038
    0
    Location:
    United States
    Vehicle:
    2004 Prius
    Model:
    N/A
    It's another form of wallet flush, not a routine maintenance item. Don't do it.
     
  15. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    The Prius doesn't have conventional brakes and you must understand the braking system. A 12 month subscription to All Data DIY is under $20

    Awhile back posted the shop manual section that correctly outlines how to bleed the brakes

    http://priuschat.com/forums/gen-ii-...em-rear-brakes-no-pressure-when-bleeding.html

    hope this helps
     
    PetBe likes this.
  16. Bikeman

    Bikeman Junior Member

    Joined:
    Apr 23, 2004
    44
    5
    0
    Vehicle:
    2006 Prius
    Hi Guys,
    OK, I had a whopper that I fixed by jumpering. My 06 has 86,000 miles and I started hearing what I thought were the squealers on the front pads. I priced getting new pads at the local Toyota ripoff dealer and at an independent. They quoted $261 and $220 respectively, so I started reading further about doing my own. I decided first to check out the pads and verify they were worn out. I pulled the RH caliper and pads, and they have a ton of meat on them. Hmmmm. Put them back together, jack up both sides of the car, start it up and put it in drive. Same noise as before. I pull the pads again, take a closer look. Ahha! A tiny pebble lodged between the caliper bracket and the rotor. Plucked it out and then here's where the adventure started! I jumped in and fired it up to test again and pressed on the brake pedal. Arrrrgh! The piston was waaaaay out of the caliper. Used a clamp on it to squeeze it back in, put it all back together. Of course, the dash is a Christmas tree. Took it for a drive and minimal braking, no ABS, nothing. Back to Prius Chat, read about jumpering, gave that a try and worked like a charm!!! Everything back to normal. Whew!!!
     
  17. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I'm not clear: did you depress the brake pedal while a pad was out of the caliper?
     
  18. Bikeman

    Bikeman Junior Member

    Joined:
    Apr 23, 2004
    44
    5
    0
    Vehicle:
    2006 Prius
    Oh yeah I did. Soooo stupid. It was one of those things that as I put my foot on the pedal my brain knew I was screwing up but my muscle memory just kept going. :(
     
  19. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Did I ever mention the time I started pouring motor oil in an automatic tranny?

    Anyway:
    And then I guess the brake fluid leaked, and the warning lights came on. Ok.

    I think as long as you don't bleed fluid you're ok doing pad changes. A little late in your case, I know. Maybe someone can comfirm that.
     
  20. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Honda, for comparison, spec's brake fluid replacement tri-yearly, regardless of mileage. I think they're concern is that it deteriorates, accumulates water.