DTC P0850-02: Park/Neutral Switch Input Circuit - General signal failure: Action

WARNING: This page is about a different car, the 2019 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

Refer to the electrical circuit diagrams and check the park/neutral signal circuit for short circuit to ground, short circuit to power, open circuit, high resistance. Repair the wiring harness as necessary
Using the Jaguar Land Rover approved diagnostic equipment, check the transmission control switch for related Diagnostic Trouble Code(s) and refer to the relevant DTC index