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Failing Alternator causing transmission shifting issues?

My vehicle (1999 Kia Sephia, 137000 miles) has had the brake and the battery indicator lights on, which from what I have read indicate an alternator problem. As my car was getting close to its last legs the shifts from one gear to the other as I was driving became harsher.



My question is, could a failing alternator cause the transmission to shift like that, and will that cause any transmission damage?
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Comments

  • edited February 2010
    Yes it can. Electronic transmissions are computer controlled, the computer requires a minimum voltage to operate. If your charging system falls below this minimum voltage requirement the transmission will go into a limp mode. You need to get this fixed ASAP.


    transman
  • edited February 2010
    Why don't you go to an auto parts store and get a free battery and alternator curb-side test? Then, if one of them needs replacing, you could take care of the problems of low voltage.
  • edited February 2010
    When I first experienced the problem yesterday, I setup an appointment to take it to my shop today. I would have yesterday, but I had to work the evening shift at work and was unable resolve it that day. I'm just glad my car was able to get me home, right after I got home my car refused to start or do anything, so I'm going have to have it towed there. I drove the car for less than a day and 40 miles , 5/6 of it highway so the transmission didn't have to shift when I reached cruising speed, I just hope it wasn't long enough to cause any permanent damage.

    Thanks for your input.
  • edited February 2010
    You can save yourself a tow bill if: you recharge the battery, and then, see if it will start. If it does, you could drive it to the repairer; or, if you are confident that the alternator is bad, and you can do the job, replace the alternator.
  • edited February 2010
    I've got AAA, so the towing is taken care of... with an 11 year old car i know i'm going need a tow every now and then, they will probably try starting it up since that is their mode of operation. I'm in Buffalo, NY essentially all the work I do on my car stops as the first flake falls since I have no indoor garage.
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