Hyundai Elantra AD Quiz
Heating, Ventilation, and Air Conditioning

PTC Heater Description and Operation

In this manual: Heating, Ventilation, and Air Conditioning
General Information — 9Engine Mechanical System — 84Engine Electrical System — 60Emission Control System — 24Engine Control System/Fuel System — 90Automatic Transmission — 92Drive Shaft and Axle — 20Suspension System — 31Steering — 20Restraints — 50Brake System — 63Body (Interior and Exterior) — 214Body Electrical System — 221Heating, Ventilation, and Air Conditioning — 71
~1min read

Description

The Positive Temperature Coefficient (PTC) heater is installed at the outlet or on the rear side of the heater core. The PTC heater is an electric heater that uses a PTC element. It is an auxiliary heating device that compensates for the lack of internal heat source in a high-efficiency diesel engine. The electric heater heats the cabin by directly heating the air passing through it. As the name implies, the element has a resistance that changes proportionally with temperature.
Operating principle: The ECM outputs the PTC ON signal and activates PTC relay 1. The heater controller then controls PTC relay 2 and PTC relay 3 at 15-second intervals. However, PTC relay 3 can operate when battery voltage is above 12.4 V. The PTC heater operates under the following conditions:
  • Battery voltage: 12.4 V or higher
  • Engine is running
  • Ambient Temperature and Coolant Temperature
Ambient
Temperature		 Coolant
Temperature		 PTC
Operation
Below -20°C (-4°F) Below 75 °C ON
10°C (50°F) Below 65 °C ON
12 °C or higher - OFF
- 80 °C or higher OFF

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