Transmission Fault Code

Hello All:

Just had the local shop run the Service Engine Soon code. They pulled P0717 - "No Low Input Turbine Speed Sensor Signal". Unfortunately they were unfamiliar with trannys. Anyone have any experience with this problem. Will it be costly to have it repaired.

I appreciate your help.

2k job - input speed sensor.
lowering engine, taking off side cover..
2-3k job in usa