DTC P0717 Input Speed Sensor Circuit - No Signal: General Description
WARNING: This page is about a different car, the 2007 Kia Optima, 2007 Kia Magentis, 2006 Kia Optima, and 2006 Kia Magentis. However, it is still accessible from the selected car via links, so may be relevant.
The input (turbine) speed sensor outputs pulse-signals according to the revolutions of the input shaft of the transmission. The TCM determines the input shaft speed by counting the frequency of the pulses. This value is mainly used to control the optimum fluid pressure during shifting.