2007 KIA CARNIVAL Workshop Manual

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

COMPONENT INSPECTION
1.Check the MAFS visually.
a. Mounting direction correct.
b. Any contamination, corrosion or damage on connector.
c. Air cleaner's clogging or wet.
d. MAFS cylinder's deforming or blocking by any foreign material.
2. Check any leakage on intake system and intercooler system.

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

COMPONENT INSPECTION
1.Connect a scantool on Diagnisis Link Connector (DLC).
2. Check MAPS output voltage at idle and IG ON.
Condition Output Voltage (V)
Idle 0.8V ~ 1.6V
IG ON 3.9V ~ 4.1V

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

COMPONENT INSPECTION
1.Turn ignition switch OFF.
2. Disconnect IATS connector.
3. Measure resistance between IATS terminals 4 and 5.
4.Check that the resistance is within the specification.
Specification: Refer to SPECIFICATION.