P1698 means that the pcm has not recieved any communication messages from the transmission control module,TCM.
The odds are that you will need a transmission control module. But there could be a wire problem. If you can when it acts up disconnect it and reconnect it to see if it will reset.
If not test the powers and grounds to the tcm.
#1 is the tcm.
here is the connector pinout
By the way do you have remote start ? because this will affect it also.