The transmission needs to be changed. It does not take a dealer to do this service. Any shop can drop the pan and change the fluid and filter. That very well may be the issue with the light.
The 700 code is for an indicator that there is a transmission code stored.
There should be another code starting with 700. Like 740, 760, or such.
You need a scan tool that can access the transmission to get the code. Some code readers will not read those codes.
Roy
Monday, February 1st, 2021 AT 2:32 AM