+ Paddle = Downshift... it finally happened to me

Discussion in 'Dodge Charger SRT Hellcat' started by dodgeboy, May 24, 2015.

  1. dodgeboy

    dodgeboy Silver Member

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    I've read a couple other threads (Challengers, I think) where people said hitting the right/+ paddle caused the transmission to downshift. This happened to me for the first time today. Twice in a row. I was driving the car in manual mode, using the paddles for about 20-30 minutes. Everything had been behaving perfectly up until the point where it happened. I was going 30-40mph and leisurely accelerating in a straight line. Hit the + paddle and it dropped from 4th to 3rd. I obviously immediately realized something wasn't right. So I hit the + paddle again. It downshifted AGAIN, from 3rd to 2nd. I let it roll like that for a few seconds and hit + again. This time it upshifted.

    I have the most current tranny flash that I'm aware of (flashed about a month ago). I guess I though that others had this issue fixed with a tranny tsb/flash. Has anyone else had this happen to them in a Charger HC?

    I'm just glad it didn't happen during spirited driving, or at a track, where it could've caused a loss of control.
     
  2. Snappycat

    Snappycat SRT Hellcat Moderator Staff Member

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    A few folks mention your situation a month or so ago. Their answers are probably buried on a thread here somewhere. Interesting to know if the flash was helpful.
     
  3. B5 Blue

    B5 Blue Platinum Member

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    Last edited: May 24, 2015
  4. fnkychkn

    fnkychkn swollen member Gold Supporting Member

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    any out of spec resistance internal to the paddle switch, on T830 circuit or erroneous interpretation by the SCM (steering column module) can affect the transmitted bus message to the TCM.
    usually, these sensed circuits operate on a MUX (multiplexed) 5V circuit. when the SCM senses a certain voltage (4.2V), it interprets it as a downshift request. when the SCM senses another voltage (2.7V), it interprets it as an upshift request.
    NOTE: the above voltages are for demonstration purposes only and are most likely incorrect.

    [​IMG]
     
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  5. Snappycat

    Snappycat SRT Hellcat Moderator Staff Member

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    In english please....
     
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  6. B5 Blue

    B5 Blue Platinum Member

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    Internal resistance in the switches or steering module can cause a wrong output signal to trans. Either faulty switches or module.
     
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  7. B5 Blue

    B5 Blue Platinum Member

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    I'm old school and like the shifter
     
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  8. fnkychkn

    fnkychkn swollen member Gold Supporting Member

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    unless it's caused by a poor connection.

    or circuit resistance like wiring or connections.


    similar issues (cruise inop, audio control inop, etc.) have been around for a couple of years on several vehicle platforms and many were corrected by steering wheel harness replacement.
     
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  9. B5 Blue

    B5 Blue Platinum Member

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    Harness isn't part of the switches then? Is the steering module also the spiral spring on Dodge?
     
  10. MoparProud

    MoparProud Silver Member

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    I don't see how it would cause a loss of control, do they not have a feature that prevents downshifts if it would result in the engine over revving?

    Like I'm pretty sure you can tap down all you want but you can't get it in 1st gear at 120.....
     
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  11. fnkychkn

    fnkychkn swollen member Gold Supporting Member

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    harness is serviced separately. yes, clockspring is part of SCM assembly.
     
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  12. B5 Blue

    B5 Blue Platinum Member

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    Thanks, noted in my word doc and also save all your wiring diagrams also;)
     
  13. rw99

    rw99 Silver Member

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    Mine has repeated this mis-shifting, even after switch replacement...

    Rich
     
  14. dodgeboy

    dodgeboy Silver Member

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    If I was applying throttle in a sweeping corner, and intended to upshift, but it downshifted, it could definitely cause a loss of control. That's not a great example, because generally you wouldn't be shifting mid-corner, but I think you get the point. Also, in wet conditions an unexpected downshift could cause problems in just about any scenario.

    I'm not saying it would grenade the engine; I know it won't downshift too far. But if I'm expecting the shift to lower the amount of torque to the wheels (upshift) and it increases the amount of torque (downshift), bad things could happen when you're dealing with the kind of power these cars have.
     
  15. dodgeboy

    dodgeboy Silver Member

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    My car was built 2/18, so this TSB was released afterwards. However, the symptoms in that TSB don't really line up with this issue. I suppose there could be other fixes that they aren't documenting.
     

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