When the P0708 code is set, it means that the TCM has detected a problem with the input/turbine speed sensor circuit. This could be due to a faulty sensor, a damaged wire, or a problem with the TCM itself.
Symptoms of a faulty input/turbine speed sensor include:
- Erratic shifting
- Loss of power
- Check engine light illumination
If you experience any of these symptoms, you should have your Kia Optima diagnosed by a qualified technician. The technician will be able to determine if the P0708 code is set and will be able to recommend the necessary repairs.