Tranny Wont shift past 2nd

I have a 1995 with the northstar. Tranny wont shift past second and it's showing the input speed sensor code.

The input speed sensor is located in the transmission so before I pull it appart I was wondering if there is any onther area to check before proceeding.

Any help apprciated.

If that code is showing, that's usually the problem. I've heard it is common on those transmissions once they get old. I have heard that you can change that solenoid without dropping the transmission down.