Hello and welcome to justanswer.com
We may have an electrical or mechanical problem with the transmission but it could also be another module like the J gate shifter. To be sure we need to hook up a Jag factory tool to read all the stored fault codes in the system. We can try a generic CAN OBD II scan tool available at most major parts stores and use this tool to scan for codes. This tool is limited to the ECM (Engine Control Module) and will not read codes from the TCM but it is worth a try. Let me know.