That code is for a communication problem between NODES and must be tested with a scan tool by PINING all the nodes, and a lab scope to identify the signals. The NODES are all located in various parts of the car. it may or may not be covered under a warranty. There is no way for you to check tranny fluid level on that.
Thanks for your question and positive feedback,
The answer I gave you was 100% correct, and this is not a DIY job. It's unfair though that the expert gets held liable because the customer didn't like the answer.
Thanks for your SUPPORT and positive feedback,