Kia Sportage: Heater / PTC Heater Description and operation
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
|
| • |
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
|

Replacement
1.
Disconnect the negative (-) battery terminal.
2.
Recover the refrigerant with a recovery/recycling/charging station.
...
Inspection
Operating Logic Test (Manual only)
Inspect the PTC operation by confirmation logic as follows;
1.
Entering
(1)
Se ...
Other information:
Removal
1.
Disconnect the battery negative terminal, and wait for at least three
minutes before beginning to work.
2.
Remove the glove box assembly.
(Refer to Body (Interior and Exterior) - "Glove box housing")
...
Normal Maintenance Schedule
- For Gasoline Engine [Except Europe (Including Russia)]
The following maintenance services must be performed to ensure good emission
control and performance. Keep receipts for all vehicle emission services to
protect your warranty. Where both m ...