PTC Heater Circuit [02/2014 - 11/2016]: Description

The air conditioning amplifier assembly sends operation signals to the PTC heater relays when the quick heater assembly operation conditions are met. Based on the signals from the air conditioning amplifier assembly, the PTC heater relays turn on, and power is supplied to the quick heater assembly installed in the air conditioning radiator assembly.

QUICK HEATER ASSEMBLY OPERATION CONDITION

Control ECU	Condition
Air Conditioning Amplifier Assembly	Power switch on (READY)
	Heater switch assembly off
	Blower switch: on
	Temperature setting: MAX HOT
	IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected)
	Engine coolant temperature: 65°C (149°F) or lower (3 PTC heater relays operating) Engine coolant temperature: 70°C (158°F) or lower (2 PTC heater relays operating) Engine coolant temperature: 75°C (167°F) or lower (1 PTC heater relay operating)
	Ambient temperature: 10°C (50°F) or lower