DTC P2610-00: ECM/PCM Internal Engine Off Timer Performance: General Description
WARNING: This page is about a different car, the 2021 Kia Soul. However, it is still accessible from the selected car via links, so may be relevant.
Engine Control Module (ECM) keeps internal counting to calculate the model values related to temperature under Ignition "OFF" condition. ECM uses this values to improve efficiency when the engine starts again.