In case the battery is removed, a number of systems have to be re-trained before they could have been functional. The first step is to take the engine cover off and unplug the cable on the negative terminus of the battery. Cooling system should be emptied and fresh coolant should be preserved to be reused, and the used antifreeze should be disposed in an effective manner. The next step is to remove battery and battery tray and identify the heater hoses, then loosen the locking clips and loosen the hoses at the core of heater inlet and outlet at the engine side of firewall and ensure that they are now attached to their original positions to ensure that the system functions. Squeegee the heater core tubes as much as possible then seal off the open tubes with a suction gun. Disassemble the lower side trim panels of the center console, as well as the user knee bolster and bracket of the driver. In models with an auxiliary heating element, remove the connector wire of the heating element and the ground wire and then remove the heating element after making sure that it is cool to prevent an accident like burns. Cover the carpeting using plastic and rags to avoid spillages of the coolant. Disconnect core coolant tubes by pushing the tab on the upper line clamp up, and screw-type clamp on the lower line up preparing to spill coolant. Once the heater core cover fasteners are loosened and the cover has been removed, the heater core should be drawn out of the housing when all the available coolant is emptied. Installation is the opposite of removal, however, the heater core pipes and core have to be surrounded by installed insulating or sealing material of the original. The last step is to refill and bleed the cooling system and then to check the engine operation.