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Drove with ebrake, now brake light/VSC/ABS

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by wtrail, Nov 10, 2020.

  1. wtrail

    wtrail Junior Member

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    I somehow managed to drive about ten miles with my parking brake engaged today. I suspect strongly that something was already up with the parking brake, because I didn't notice any issues accelerating or turning. What I did notice was my dashboard lit up all at once - BRAKE, VSC, ABS. I stopped the car and poked around... I noticed an electrical hum from under the hood which I can't quantify, but it may be normal - I've never had cause to stick my head in there when the engine was on before. Brake fluid was normal.

    Total ineffectiveness of the e-brake notwithstanding, brake performance seems completely normal. Braking is smooth, tight, and reliable, and does not affect the heading of the car.

    I used OBD Fusion to read the codes, and got the following:

    C0200 - Front Speed Sensor RH Circuit
    C0205 - Front Speed Sensor LH Circuit
    C1236 - Foreign Object is Attached on Tip of Front Speed Sensor LH
    C1343 - Hydraulic System(RR)

    I've booked time with my mechanic to have a look at the car, but that won't be until the 25th unfortunately. Does anybody have a sense of what's wrong, and if so, is it something I might be able to fix myself sooner?
     
    #1 wtrail, Nov 10, 2020
    Last edited: Nov 10, 2020
  2. wtrail

    wtrail Junior Member

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    I did a little more testing and found that if I put my car in Drive and floor the gas pedal, my brakes keep the car completely immobilized until I release the brakes 3/4th of the way or so. At that point the car starts to creep forward with a faint ticking/groaning sound coming from the brakes.
     
  3. bisco

    bisco cookie crumbler

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    welcome!

    try disconnecting the 12v neg for a minute
     
  4. pasadena_commut

    pasadena_commut Senior Member

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    The heat from the constantly engaged brake most likely cooked something nearby. This is the sort of event which can result in warped rotors/drums, melted brake lines, or fried sensors. Was this highway miles? I wouldn't have thought 10 miles of stop and go city driving would have caused damage, but 10 miles at 80 mph with a brake dragging might.
     
  5. wtrail

    wtrail Junior Member

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    This was about nine miles of gentle rural driving between towns, and a mile of stop and go town driving. I really don't know how much heat the brake could have generated, as the car accelerated well and coasted as well as normal. On the other hand, the brake light probably doesn't lie, and I messed SOMETHING up.

    I tried this a few times with no result. But I then tried one more time to clear the codes with my OBDII dongle, this time with the car in IGN-ON mode, and the lights disappeared and have yet to come back on. Maybe I'll get away with nothing worse than a handbrake cable tightening when I bring it into the shop next week...
     
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  6. pasadena_commut

    pasadena_commut Senior Member

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    Drive it a couple of miles from cold, preferably without applying the brakes at all. Then stop and feel all the wheels near the axle. If this event screwed something up so that a brake is now dragging that wheel will be hotter than the others. If you do not find that, and you probably won't, then it should be OK to drive until your appointment. If on the other hand you do find a hot wheel maybe better to use another car until it can be fixed.
     
  7. wtrail

    wtrail Junior Member

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    Did this and didn't feel any warmth- the car seems to be running fine, with brake performance remaining good. I'm going to drive it as needed until my appointment, but I've used engine braking on a few occasions to help ease the strain on the brakes... it's probably doing more for my emotional state than the car, but every little bit helps!
     
    #7 wtrail, Nov 16, 2020
    Last edited: Nov 16, 2020
  8. wtrail

    wtrail Junior Member

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    Final update for anyone else with similar issues – after clearing the codes the lights never came back. Car drove fine until my mechanic could look at it, but it turned out I did wear down the brake pads a decent bit, and it cost $200 or so to replace them. The moral of the story is, a lack of brake burn odor doesn’t mean you didn’t burn them off!