DTC P0110 Intake Air Temperature Circuit
DTC P0112 Intake Air Temperature Circuit Low Input
DTC P0113 Intake Air Temperature Circuit High Input
DESCRIPTION
The Intake Air Temperature (IAT) sensor, mounted on the Mass Air Flow (MAF) meter, monitors the IAT.
The IAT sensor has a built-in thermistor with a resistance that varies according to the temperature of the intake air. When the IAT is low, the resistance of the thermistor increases. When the temperature is high, the resistance drops. These variations in resistance are transmitted to the ECM as voltage changes (see Fig. 1).
The IAT sensor is powered by a 5 V applied from the THA terminal of the ECM, via resistor R.
Resistor R and the IAT sensor are connected in series. When the resistance value of the IAT sensor changes, according to changes in the IAT, the voltage at terminal THA also varies. Based on this signal, the ECM increases the fuel injection volume when the engine is cold to improve driveability.
HINT: When any of DTCs P0110, P0112 and P0113 are set, the ECM enters fail-safe mode. During fail-safe mode, the IAT is estimated to be 20C (68F) by the ECM. Fail-safe mode continues until a pass condition is detected.
DTC No. |
Proceed to |
DTC Detection Condition |
Trouble Area |
P0110 | Step 1 | Open or short in Intake Air Temperature (IAT) sensor circuit for 0.5 seconds (1 trip detection logic) |
|
P0112 | Step 4 | Short in Intake Air Temperature (IAT) sensor circuit for 0.5 seconds (1 trip detection logic) |
|
P0113 | Step 2 | Open in Intake Air Temperature (IAT) sensor circuit for 0.5 seconds (1 trip detection logic) |
|
HINT: When any of these DTCs are set, check the IAT by selecting the following menu items on the intelligent tester: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / INTAKE AIR.
MONITOR DESCRIPTION
The ECM monitors the sensor voltage and uses this value to calculate the Intake Air Temperature (IAT).
When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a malfunction in the IAT sensor and sets a DTC.
Example: If the sensor voltage output is -40C (-40F) for 0.5 seconds or more, the ECM determines that there is an open in the IAT sensor circuit, and sets DTC P0113. Conversely, if the voltage output is more than 140C (284F) for 0.5 seconds or more, the ECM determines that there is a short in the sensor circuit, and sets DTC P0112.
If the malfunction is not repaired successfully, a DTC is set 0.5 seconds after the engine is next started.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
P0110:
P0112:
P0113:
COMPONENT OPERATING RANGE
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
1 READ VALUE OF INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)
Standard: Same as actual Intake Air Temperature (IAT).
Result
HINT:
2 READ VALUE OF INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)
Standard: 140C (284F) or higher
3 CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
Standard resistance: Check for open
Check for short
REPLACE ECM
4 READ VALUE OF INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)
Standard: -40C (-40F)
5 CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
Standard resistance
REPLACE ECM
DTC check / clear
NOTICE:
All the stored DTCs and freeze frame data are erased if:
the ECM is changed from normal mode to check mode
or vice versa; or 2) the ignition switch is turned from ON
to ACC or off while in check mode.
Before changing modes, always check and make a note
of any DTCs and fr ...
Active Control Engine Mount System
DESCRIPTION
LOCATION
The Active Control Engine Mount (ACM) system decreases engine vibration at
engine idling using the
ACM VSV. The VSV is controlled by a pulse signal transmitted to the VSV from the
ECM. The frequency
of this pulse signal is matched to the engine speed to decrease engi ...
Headlight leveling switch
ON-VEHICLE INSPECTION
1. HEADLIGHT LEVELING SWITCH
Connect the battery positive (+) lead to the terminal
1 and the battery negative (-) lead to the terminal 5.
Measure the resistance between the terminal 4 and
the battery negative (-) lead when headlight leveling
switch ...