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Engine Coolant
Temperature Sensor (ECTS)
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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
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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.
Page 276 of 1575
Accelerator Position Sensor(APS)
Page 277 of 1575
2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRICIPLE
Accelerator Position Sensor (APS) is installed on the accelerator pedal module and detects the rotation angle of the
accelerator pedal. The APS is one of the most important sensors in engine control system, so it consists of the two
sensors which adapt individual sensor power and ground line. The second sensor monitors the first sensor and its
output voltage is half of the first one. If the ratio of the sensor 1 and 2 is out of the range (approximately 1/2), the
diagnostic system judges that a malfunction has occurred.
SPECIFICATION
Pedal Position Output Voltage (V) [Vref = 5.0V]
APS1 APS2
C.T 0.7 ~ 0.8V 0.29 ~ 0.46V
W.O.T 3.85 ~ 4.35V 1.93 ~ 2.18V
Item Sensor Resistance
APS1 0.7 ~ 1.3kΩ at 20°C (68°F)
APS2 1.4 ~ 2.6kΩ at 20°C (68°F)
CIRCUIT DIAGRAM
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Heated Oxygen Sensor(HO2S)
Page 281 of 1575
2007 > 2.7L V6 GASOLINE >
INSPECTION
FUNCTION AND OPERATION PRICIPLE
Heated Oxygen Sensor (HO2S) consists of zirconium and alumina and is installed on upstream and downstream of the
Manifold Catalyst Converter (MCC). After it compares oxygen consistency of the atmosphere with the exhaust gas, it
transfers the oxygen consistency of the exhaust gas to the PCM. When A/F ratio is rich or lean, it generates
approximately 1V or 0V respectively. In order that this sensor normally operates, the temperature of the sensor tip is
higher than 370°C (698°F). So it has a heater which is controlled by the PCM duty signal. When the exhaust gas
temperature is lower than the specified value, the heater warms the sensor tip.
SPECIFICATION
A/F Ratio Output Voltage (V)
RICH 0.80 ~ 0.92
LEAN 0.1
Item Specification
Page 285 of 1575
CVVT Oil Temperature Sensor(OTS)