P0700 states the computer detected a transmission malfunction.
Unfortunatley, this is a rather vague code.
Many problems can cause this code to set.
The best way to diagnose this is thorugh data stream using a scantool and a few voltage checks.
Try swapping Electronic Automatic Transaxle (EATX) relay with another relay.
Check fuse #17 in PDC
Check both the transmission input and output shaft speed reading on scantool.
Check that the solenoids are working correctly and that the tcc solenoid locks and unlocks correctly using data stream. Ohm test the solenoids at the transmission connector.
Remove the pan, check for contaminants and condition of filter.
If all looks good, a transmission overhaul.
Most common problems are speed sensors and faulty solenoids. It is suggested that if a faulty speed sensor is found you replace the sensors in pairs. The solenoids are serviced as the solenoid pack and can not ba replaced individually.