Possible Causes

WARNING: This page is about a different car, the 2018 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

The Powertrain control module detected failure when comparing two or more input parameters for plausibility
The brake pedal switch signal received over CAN is defective
Brake pedal switch detached from pedal box while electrically connected
Brake pedal switch adjustment incorrect
Brake pedal switch harness failure
Connector is disconnected, connector pin is backed out, connector pin corrosion
Brake pedal switch failure