Runner 250 Standard Motor Not Spinning

Discussion in 'Walkera Runner 250' started by dorrisant, Sep 21, 2017.

  1. dorrisant
    Offline

    dorrisant New Member

    Joined:
    Apr 2, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Ratings:
    +0 / 0
    I have a standard 250 here. When flying yesterday, I sat it down in tall grass and forgot to turn off the switch that keeps the motors spinning (to avoid flip of death... 6% throttle). Anyway, when I got to it, it was burried deep in the grass and when I freed it, I noticed the right-rear motor not spinning.

    Today I swapped motors from the corner in question to the opposite corner. Result - Same as before, same motor will spin with the other ESC. The known-good motor would not spin in the right-rear position. So I swapped ESCs thinking that the problem should follow the ESC since the motor was not bad from the prior test. Not so - The right-rear motor will not spin even with know-good ESC and motor. So it seems relative to this right-rear position. Does this sound like a bad main board? Or could it be the flight controller?

    I pulled the top plate off to address the ESC connector but found no problem there. I pulled out all of the original solder and reflowed the joints between the main board and connector. Upon reassembly I got the same results.

    I did notice something and wondered if it might be a clue to those of you with more experience with the Runner. The motor in the questionable right-rear position will jump on the first two pulses when powering up, all motors jump on the first two pulses as is normal. During the following three pulses this right-rear motor doesn't move yet the other three move.

    I have tried to help the motor start while throttle is applied with no luck. It does spin freely by hand as do the other three motors. I'm just wondering if anyone has had a similar problem and what the outcome was...

    Thanks for reading!
    Tony

     
    Last edited: Sep 22, 2017
  2. bjr981s
    Offline

    bjr981s Moderator Staff Member

    Top Poster Of Month

    Joined:
    Sep 19, 2015
    Messages:
    5,065
    Likes Received:
    314
    Trophy Points:
    83
    Location:
    Sydney, Australia
    Ratings:
    +408 / 13
    Sounds like the power board to me or the FC ribbon connector. Your diagnosis method is correct. But it could also be that you have dislodged the Ribbon cable or filled it's connector full of debris.

    Try removing and cleaning the FC ribbon cable with isopropyl alcohol. Check for any damage or cracks.
     
  3. dorrisant
    Offline

    dorrisant New Member

    Joined:
    Apr 2, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Ratings:
    +0 / 0
    Thank you for the response. I will check the ribbon cable before I buy another main board.
     

Share This Page