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Check engine light came on. Giving this code P1817. Can anyone tell me what this code means? Thanks.
Don't quote me on this, but......I'm pretty sure that it is a failure of one of the trans pressure switches or circuits. The A4 trans has a sensor plate attached to the valve body which provides feedback to the pcm which tells the pcm when a particular fluid circuit is fully pressurized. (or shift is complete). It also uses the switches for a complex adaptive learn function which tells the pcm when components of the trans are wearing so that it can maintain shift timing by increasing fluid pressure to compensate for wear...Again, don't quote me here but I seem to remember that when a failure occurs here (if the trans dosen't go into limp mode) it commands full line pressure to help the trans get you to service....not good to drive around this way...
Thanks for the info. I am not driving it--thankfully I have a second vehicle that I can drive. Going to play in the snow til after the new year and then I will worry about getting it fixed. I appreciate all the answers anyone might have.