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

VSC ABS BRAKE LIGHT ON

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by art1saf, Nov 28, 2013.

  1. art1saf

    art1saf Junior Member

    Joined:
    Jan 6, 2013
    13
    1
    0
    Vehicle:
    2005 Prius
    Model:
    Plug-in Base
    I had replaced the skid plate module as it was defective with a unit from an 2007. The brakes work perfectly but the ABS, VSC ( !) light are on. The codes on the mechanics computer show non communication between other modules. Can anybody please help.
    Thank you, Arthur
     
  2. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    337
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    Without the mini VCI to do this sort of thing, you need to clear the DTC's with another chicken dance:

    1. Short pins 4 and 13 of the OBDII port and then make car Ready.
    2. Press the brake pedal 8 times within 5 seconds.
    3. lights should go off if no problems remain.

    These brake codes are stored in nonvolatile memory and can't be cleared by removing the 12V.
     
    RachaelH likes this.
  3. art1saf

    art1saf Junior Member

    Joined:
    Jan 6, 2013
    13
    1
    0
    Vehicle:
    2005 Prius
    Model:
    Plug-in Base
    Thank you for your reply. I have not as yet given this information to my mechanic. He did inform me that the codes in my computer had to do with the loss of communication between modules. I believe they where in the 1300's. He had tried to clear them with a special computer but the lights refused to go out. The car's brakes are working perfectly. Any additional input would be greatly appreciated. Arthur
     
    dougz4m likes this.
  4. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    337
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    I would try the procedure in my post before doing anything else. The Prius requires a device that works with those lines (Pin 4 and 13 on the connector) to clear the codes. If the generic device that your mechanic used does not know how to do that, it won't clear those brake codes. A very common situation that people report here is trying to use generic OBDII readers on the Prius. It is really hit or miss to use such, and you never know for sure what is happening, as they can report false readings. Techstream is the only way to go in order to be sure.

    It may be that the codes are getting cleared but come back because there is still a problem. Even if the brakes work, there can still be a malfunction.

    Otherwise, the 12V battery is suspect, as it can cause brake related glitches at start up if the voltage dips too low. This is especially true after the car has been worked on and has had the doors left open, lights on, etc. Make sure the battery is fully charged.
     
    dougz4m likes this.