Post Heating
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.
Post heat is the length of time the glow plugs operate after the engine starts. The ECM controls the post heating time based on ECT sensor output. The post heat phase reduces engine noise, improves idle quality and reduces hydrocarbon emissions.
Preheating is followed by the post heating phase as soon as the engine has started. The post heating phase depends upon how the vehicle is driven.