DTC P1707-77: Transfer Case Neutral or Park/Neutral Indication Circuit - Commanded position not reachable: Action

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2017 Jaguar XJR, 2017 Jaguar XJ, 2016 Jaguar XJR, 2016 Jaguar XJ, and 2015 Jaguar XJR. However, it is still accessible from the selected car via links, so may be relevant.

Check the integrity of the emergency park release. Rectify as necessary
Check the integrity of the parklock mechanism. Using the Jaguar Land Rover approved diagnostic equipment, clear the DTCs and perform a road test. Check the parklock mechanism by engaging and disengaging the parklock several times. Rectify as necessary
Using the Jaguar Land Rover approved diagnostic equipment, clear the DTCs and retest. If the fault persists, install a new transmission control module