Hyundai Ioniq (AE): Hybrid Motor Cooling System / Radiator. Components and components location

Changing the Coolant and Performing Air Bleeding    Never remove the cap while the engine is hot. When you remove the cap from the reservoir, hot coolant may spew out due to the high pressure, causing serious injury.

Removal1.Remove the 12 V battery (-) cable.2.Remove the undercover.(Refer to Engine Mechanical System - "Engine Room Undercover".)3.Drain the coolant from the hybrid cooling system.