DTC B1387-19: A/C Cooling Electric Expansion Valve Circuit Current Above Threshold [08/2023 - ]: Description

The cooling electric expansion valve (cooler expansion valve) is installed on the inlet pipe of the No. 1 cooler evaporator and is closed when the ignition switch is turned off. When the ignition switch is turned to ON, heat pump air conditioning control is performed to operate the stepping motor and adjust the valve opening angle of the cooling electric expansion valve (cooler expansion valve). When heat pump air conditioning control is performing heating/defrosting, the cooling electric expansion valve (cooler expansion valve) is closed according to signals from the heat pump ECU assembly. When heat pump air conditioning control is performing cooling/serial heating/parallel dehumidification heating/cooling battery cooling, the cooling electric expansion valve (cooler expansion valve) is adjusted to the appropriate control opening angle according to signals from the heat pump ECU assembly. When heat pump air conditioning control is performing single battery cooling, the cooling electric expansion valve (cooler expansion valve) is opened slightly according to signals from the heat pump ECU assembly.