Hyundai Elantra: Heater / PTC Heater Description and Operation

Hyundai Elantra AD (2016-2020) Service Manual / Heating, Ventilation and Air Conditioning / Heater / PTC Heater Description and Operation

Description

The PTC (Positive Temperature Coefficient) heater is installed at the exit or the backside of heater core.

The PTC heater is an electric heater using a PTC element as an auxiliary heating device that supplements deficiency of interior heat source in highly effective diesel engine. The electric heater heats up the interior by directly heating the air that passes through the heater. The name itself implies that the element has a proportional resistance change sensitive to temperature.

Operation Principle

ECM outputs a PTC ON signal and operates PTC relay 1. Then heater controller operates PTC relay 2 and PTC relay 3 with an interval of 15 seconds.

However, PTC relay 3 can be operated while battery voltage is above 12.4V.

Operating Condition

PTC heater operates according to the following conditions;

•	Battery voltage: 12.4V or above

•	Engine : Running

•	Ambient temperature and coolant temperature

Ambient Temperature	Coolant Temperature	PTC Operation
Below -20°C (-4°F)	Below 75°C (167°F)	ON
10°C (504°F)	Below 65°C (149°F)	ON
12°C (53.6°F) or above	-	OFF
-	80°C (176°F) or above	OFF

Heater Core Repair procedures

Replacement 1. Disconnect the negative (-) battery terminal. 2. Remove the heater and blower assembly. (Refer to Heater - "Heater Unit") 3. Remove the heater core cover (A) after loosen ...

PTC Heater Repair procedures

Inspection Operating Logic Test (Manual only) Inspect the PTC operation by confirmation logic as follows. 1. Entering (1) Set the Floor mode and maximum heating position. (2) Turn off the ...

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