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Cat 257b parking brake wont release really need help

kmartin2 · 2016-10-26 17:22

I really need some help !!! i have cat 257b and the parking brake wont release.When i get in the machine and turn the key to the on position the display on the machine beeps and all of the panel lights come on. however when i turn the machine on the parking brake light never illuminates. Then when i press the parking brake switch the seat switch blinks and the parking brake light very faintly blinks with it.

Replies10
  1. #1Nige2016-10-27 08:32

    A machine Serial Number would be a very good start. From your description it sounds like a wiring fault. How good are you at testing electrical circuits and do you have a multimeter..?

  2. #2kmartin22016-10-27 09:22

    Serial number slk01925

  3. #3kmartin22016-10-27 09:34

    I have a multimeter and I've been troubleshooting but all the troubleshooting things I have found, none of them say anything about the parking brake light being off. Which leads me to believe it's the ecm. I read that those go bad sometimes the machine has 1362 hrs.

  4. #4kmartin22016-10-27 09:40

    I have tried jumping solenoid, and checking for resistance, and continuity

  5. #5Nige2016-10-27 10:36

    Would a copy of the appropriate Electrical Schematic help you..?

  6. #6Mark2502016-10-27 21:56

    Hi not sure what you mean (key on all lights on ,is the brake light on at this time or does it not come on with key in on position and machine running the faint brake indicator light sounds like a reflection from the seat indicator light which is right next to the brake indicator. to check that the light is working disconnect the blue wire from terminal #70 at the interlock ECM and ground it if the light comes on you have a possible bad ECM, if the light does not come on try and ground the blue wire at pin#4 at the indicator panel. you need the light working for basic diagnostic tests

  7. #7kmartin22016-12-29 10:12

    The parking brake will light up when the machine goes through its check but when the machine is running it does not

  8. #8kmartin22016-12-31 16:42

    So what would make the parking brake light up when going through checks but turn off after

  9. #9kmartin22017-01-08 23:14

    I bought a new ecm and that fixed the parking lamp. Now when I release the parking brake the arm and bucket move fine but the tracks don't wanna move like the brake is still engaged can anyone help mwoth that issue ?

  10. #10Oldstyl32024-10-28 23:12

    I know it’s a old question but you ever figure out the problem