sensor KIA CARNIVAL 2007 Repair Manual

Mass Air Flow Sensor(MAFS)

2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRINCIPLE
Mass Air Flow Sensor (MAFS) is a hot - film type sensor and is located in between the air cleaner and the throttle
body. It consists of a tube, a sensor assembly and honeycomb cell and detects intake air quantity flowing into the
intake manifold. Air flows from the air cleaner assembly through the honeycomb cell and over the hot film element. At
this time, heat transfer is generated by convection and this sensor loses its energy. This sensor detects the mass air
flow by using the energy loss and transfers the information to the PCM by frequency. The PCM calculates fuel quantity
and ignition timing.
SPECIFICATION
Air Flow (kg/h) Output Frequency (Hz)
12.6 kg/h 2,617Hz
18.0 kg/h 2,958Hz
23.4 kg/h 3,241Hz
32.4 kg/h 3,653Hz
43.2 kg/h 4,024Hz
57.6 kg/h 4,399Hz
72.0 kg/h 4,704Hz
108.0 kg/h 5,329Hz
144.0 kg/h 5,897Hz
198.0 kg/h 6,553Hz
270.0 kg/h 7,240Hz
360.0 kg/h 7,957Hz
486.0 kg/h 8,738Hz
666.0 kg/h 9,644Hz
900.0 kg/h 10,590Hz
CIRCUIT DIAGRAM

Manifold Absolute Pressure Sensor (MAPS)

2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRICIPLE
Manifold Absolute Pressure Sensor (MAPS) is speed- density type sensor and is installed on the surge tank. This
MAPS senses absolute pressure in surge tank and transfers this analog signal proportional to the pressure to the
PCM. The PCM calculates the intake air quantity and engine speed based on this signal. This MAPS consists of
piezo - electric element and hybrid IC that amplifies the element output signal. The element is silicon diaphragm type
and adapts pressure sensitive variable resistor effect of semi- conductor. 100% vacuum and the manifold pressure
applies to both sides of it respectively. That is, this sensor outputs the silicon variation proportional to pressure change
by voltage.
SPECIFICATION
Pressure(kPa) Output Voltage (V)
20.0 0.79
46.66 1.84
101.32 4.0
CIRCUIT DIAGRAM

Intake Air Temperature Sensor(IATS)

2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRICIPLE
Intake Air Temperature Sensor (IATS) is installed inside the Mass Air Flow Sensor (MAFS) and detects the intake air
temperature. To calculate precise air quantity, correction of the air temperature is needed because air density varies
according to the temperature. So the PCM uses not only MAFS signal but also IATS signal. This sensor has a
Negative Temperature Coefficient (NTC) and its resistance is in inverse proportion to the temperature.
SPECIFICATION
Temperature Resistance (kΩ)
°C °F
- 40 - 40100.87
- 20 -428.58
0 329.40
10 505.66
20 683.51
40 104 1.47
60 140 0.67
80 176 0.33
CIRCUIT DIAGRAM

Engine Coolant
Temperature Sensor (ECTS)

2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRICIPLE
Engine Coolant Temperature Sensor (ECTS) is located in the engine coolant passage of the cylinder head for
detecting the engine coolant temperature. The ECTS uses a thermistor whose resistance changes with the
temperature. The electrical resistance of the ECTS decreases as the temperature increases, and increases as the
temperature decreases. The reference 5 V in the PCM is supplied to the ECTS via a resistor in the PCM.That is, the
resistor in the PCM and the thermistor in the ECTS are connected in series. When the resistance value of the
thermistor in the ECTS changes according to the engine coolant temperature, the output voltage also changes. During
cold engine operation the PCM increases the fuel injection duration and controls the ignition timing using the
information of engine coolant temperature to avoid engine stalling and improve drivability.
SPECIFICATION
Temperature Resistance(kΩ)
°C °F
- 40 - 4048.14
- 20 -414.13 ~ 16.83
0 325.79
20 682.31 ~ 2.59
40 104 1.15
60 140 0.59
80 176 0.32
CIRCUIT DIAGRAM

COMPONENT INSPECTION
1.Turn ignition switch OFF.
2. Disconnect ECTS connector.
3. Remove the ECTS.
4. After immersing the thermistor of the sensor into engine coolant, measure resistance between ECTS terminals 1
and 3.
5.Check that the resistance is within the specification.
Specification: Refer to SPECIFICATION.

Accelerator Position Sensor(APS)