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ABS, VSC, ((!)), and Brake lights on.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by awommy, Jan 26, 2016.

  1. awommy

    awommy Junior Member

    Joined:
    May 3, 2015
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    Location:
    WA
    Vehicle:
    2004 Prius
    Model:
    II
    I replaced my rear brake shoes this past weekend. Immediately after I replaced them, the ABS, VSC, ((!)), and Parking Brake lights came on. I had not read that I should've disconnected the 12V battery before changing the shoes, so I wonder if that's related to the issue. I've read through as many threads here that I could dig up, but I still have questions. Here is what I know so far (please forgive some of my terminology. I'll be as accurate as possible):

    Car Info:
    • 2004
    • 210k miles
    • Original 12V battery
    Relevant Info:
    • While replacing the shoes, one of the seals(?) (rubber part that slid over the piston(?)) slid off. I put it back on, and have checked for any fluids leaking, and have found none. I may pull the rotors off and check this again, though.
    • There were no DTCs logged prior to the shoe replacement.
    • Battery has shown no signs of dying, although I am going to check the voltage on it after I post this.
    • I tried jumping the pins, and I get the following flash codes (I tried resetting, but they came back immediately):
      • ABS: 4-2
      • VSC: 4-5
      • ((!)): 6-5
      • I tried finding information on these flash codes, but have found nothing...
    • My CHS Tank was damaged in an accident a few years ago. I just replaced the CHS tank and the Inverter Coolant Pump within the last 12 months. It is still running when I power the car on and off as it should. I also jumped the fuse with a paperclip to double check that it runs.
    • My brake fluid levels are fine right now.

    Possibly unrelated to the lights, but applying the parking brake is very easy. I don't think I adjusted the star adjuster enough. This is my first time messing with drum brakes, so it's possible I didn't adjust that correctly. Are these self-adjusting, or do I need to go back and adjust them by hand?

    Also, I'd like to believe that it's not related to the battery, because there's been no indication of it dying before, and the lights came on immediately after I replaced the brake shoes... But I'll still go test the voltage on it.
     
    #1 awommy, Jan 26, 2016
  2. awommy

    awommy Junior Member

    Joined:
    May 3, 2015
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    Location:
    WA
    Vehicle:
    2004 Prius
    Model:
    II
    I used a multimeter rather than the built in function. Here's the voltage readings:
    with the car off: 12.3V
    after pressing start button once (not ready): 12.12-12.13V
    after pressing start button twice (not ready): 11.87V (coolant pump did run, dashcam was still plugged in, but fans were off...if that makes any difference).
    Ready: 14.01V
    I don't think the issue is with the battery.
     
    #2 awommy, Jan 26, 2016
  3. WilDavis

    WilDavis Senior Member

    Joined:
    Feb 4, 2014
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    Location:
    Top RH Corner of RH Coast on L side of The Pond
    Vehicle:
    2009 Prius
    Model:
    II
    Just FYI (…and my apologies for coming to the discussion late) I attended the 2GoB4 PriusChat Get-Together back in the fall of 2014 when it was in my area, and I seem to remember in one of the talks, it being mentioned that while there are many things which the DIY owner can easily fix/repair/maintain on the Prius, there are certain things which require specialist equipment and knowledge, and an example given was bleeding/adjusting brakes! Perhaps someone with more knowledge than I might chime in? (…please!) - hope this helps - Wil (BTW: Welcome to PriusChat!)
     
    #3 WilDavis, Jan 26, 2016
  4. awommy

    awommy Junior Member

    Joined:
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    Location:
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    Vehicle:
    2004 Prius
    Model:
    II
    I've been reading through more threads, and it looks like maybe this is an issue related to the skid control ECU? Is it possible I threw that off by tapping the drums with a hammer to loosen them?

    If it is the skid control ECU, is there a way to reset this computer? I would rather not replace it if I don't have to...
     
    #4 awommy, Jan 27, 2016
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Use Mini VCI to read the fault codes posted by the skid control ECU. When you are ready to clear the codes, use Mini VCI.

    If you insist on not acquiring Mini VCI, then you can short pins 4 to 13 on the OBD-II connector, there are several posts about how to do that.

    The drum brakes will self-adjust only a very tiny amount at a time, so if you did not correctly adjust the rear brake shoe spacing to the drums, you need to go back and do that now.

    There is no need to hit the drums to release them. That is the purpose of the two threaded holes in each drum. You are supposed to insert two metric screws (I believe 6 mm is the correct size; if not then 8 mm) into those holes to force a drum off the brake assembly.
     
    #5 Patrick Wong, Jan 29, 2016
  6. awommy

    awommy Junior Member

    Joined:
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    Location:
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    Vehicle:
    2004 Prius
    Model:
    II
    I did just purchase a Mini VCI, so I'm just waiting on that to come.

    In the meantime, As I posted in the first post, I did short pins 4-13, and read the flash codes, though I haven't been able to interpret them.

    I will remember to use the threaded holes next time I do this. I didn't realize their purpose before.
     
    #6 awommy, Jan 29, 2016
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