Description
DATA TROUBLE CODE: P0110SYSTEM: Intake Air Temperature Circuit
CIRCUIT DESCRIPTION
The Intake Air Temperature Sensor is built into the aIr Flow Meter and senses the intake air temperature.
A thermistor built in the sensor changes the resistance value according to the intake air temperature.
The lower the intake air temperature, the greater the thermistor resistance value, and the higher the intake air temperature, the lower the thermistor resistance value.
The Intake Air Temperature Sensor is connected to the Engine Control Module. The 5 volt power source voltage in the Engine Control Module is applied to the Intake Air Temperature Sensor from the terminal THA via a resistor R.
That is, the resistor R and the Intake Air Temperature Sensor are connected in series. When the resistance value of the Intake Air Temperature Sensor changes in accordance with changes in the intake air temperature, the potential at terminal THA also changes. Based on this signal, the Engine Control Module increases the fuel injection volume to improve driveability during cold engine operation.
If the Engine Control Module records the Diagnostic Trouble Code "P0110", it operates the fail safe function in which the intake temperature is assumed to be 20°C (68°F).
Intake Air Temperature: Resistance / Voltage
-20°C (-4°F): 16.2 k ohms / 4.3 volts
0°C (32°F): 5.9 k ohms / 3.4 volts
20°C (68°F): 2.5 k ohms / 2.4 volts
40°C (104°F): 1.1 k ohms / 1.4 volts
60°C (140°F): 0.6 k ohms / 0.9 volts
80°C (176°F): 0.3 k ohms / 0.5 volts
100°C (212°F): 0.1 k ohms / 0.2 volts
DIAGNOSTIC TROUBLE CODE DETECTING CONDITION
- Open or short in Intake Air Temperature Sensor circuit.
TROUBLE AREA
- Open or short in Intake Air Temperature Sensor circuit.
- Intake Air Temperature Sensor.
NOTE: After confirming Data Trouble Code P0110 use the OBDII scan tool or LEXUS hand-held tester to confirm the intake air temperature from "CURRENT DATA".
Temperature displayed -40°C (-40°F): open circuit.
Temperature displayed 120°C (248°F) or more: short Circuit.