P0113
2UR-GSE ENGINE CONTROL: SFI SYSTEM: P0112, P0113: Intake Air Temperature Circuit Low Input
P0113 - Intake Air Temperature Circuit High Input
DESCRIPTION
- The intake air temperature sensor, in the mass air flow meter, monitors the intake air temperature. The intake air temperature sensor has a built-in thermistor with a resistance that varies according to the temperature of the intake air. When the intake air temperature 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 intake air temperature sensor is powered by a 5 V supply from the THA terminal of the ECM, via resistor R.
- Resistor R and the intake air temperature sensor are connected in series. When the resistance value of the intake air temperature sensor changes, according to changes in the intake air temperature, 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 P0112 and P0113 are set, the ECM enters fail safe mode. During fail safe mode, the intake air temperature is estimated to be 20°C (68°F) by the ECM. Fail safe mode continues until a pass condition is detected.
HINT
When any of these DTCs are set, check the intake air temperature by entering the following menus: Powertrain / Engine / Data List / Intake Air.
MONITOR DESCRIPTION
The ECM monitors the sensor voltage and uses this value to calculate the intake air temperature. When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a malfunction in the intake air temperature sensor and sets a DTC.
Example:
If the sensor output voltage is more than 4.91 V for 0.5 seconds or more, the ECM determines that there is an open in the intake air temperature sensor circuit, and sets DTC P0113. Conversely, if the output voltage is less than 0.18 V 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
P0112
P0113
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the Techstream on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.
4. Turn the engine switch off and wait for at least 30 seconds.
5. Turn the engine switch on (IG) and turn the Techstream on.
6. Wait 0.5 seconds or more.
7. Enter the following menus: Powertrain / Engine / Trouble Codes.
8. Read the pending DTC.
HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
9. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
10. Input the DTC: P0112 or P0113.
11. Check the DTC judgment result.
HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
12. If the test result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
- If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
PROCEDURE
1. READ VALUE USING TECHSTREAM (INTAKE AIR)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / Intake Air.
(e) Read the value displayed on the Techstream.
Standard:
Same as actual intake air temperature.
Result:
HINT
- If there is an open circuit, the Techstream indicates -40°C (-40°F).
- If there is a short circuit, the Techstream indicates higher than 128°C (262°F).
B -- READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
C -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems
A -- Continue to next step.
2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)
(a) Disconnect the mass air flow meter connector.
(b) Connect terminals THA and E2 of the mass air flow meter wire harness connector.
(c) Connect the Techstream to the DLC3.
(d) Turn the engine switch on (IG).
(e) Turn the Techstream on.
(f) Enter the following menus: Powertrain / Engine / Data List / Intake Air.
(g) Read the value displayed on the Techstream.
Standard:
Higher than 128°C (262°F)
(h) Reconnect the mass air flow meter connector.
NG -- READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM)
OK -- REPLACE MASS AIR FLOW METER Removal
3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM)
(a) Disconnect the mass air flow meter connector.
(b) Connect terminals THA and E2 of the ECM connector.
HINT
Before checking, do visual and contact pressure checks on the ECM connector.
(c) Connect the Techstream to the DLC3.
(d) Turn the engine switch on (IG).
(e) Turn the Techstream on.
(f) Enter the following menus: Powertrain / Engine / Data List / Intake Air.
(g) Read the value displayed on the Techstream.
Standard:
Higher than 128°C (262°F)
(h) Reconnect the mass air flow meter connector.
NG -- REPLACE ECM Removal
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)
4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
(a) Disconnect the mass air flow meter connector.
(b) Connect the Techstream to the DLC3.
(c) Turn the engine switch on (IG).
(d) Turn the Techstream on.
(e) Enter the following menus: Powertrain / Engine / Data List / Intake Air.
(f) Read the value displayed on the Techstream.
Standard:
-40°C (-40°F)
(g) Reconnect the mass air flow meter connector.
NG -- READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN ECM)
OK -- REPLACE MASS AIR FLOW METER Removal
5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN ECM)
(a) Disconnect the mass air flow meter connector.
(b) Disconnect the ECM connector.
(c) Connect the Techstream to the DLC3.
(d) Turn the engine switch on (IG).
(e) Turn the Techstream on.
(f) Enter the following menus: Powertrain / Engine / Data List / Intake Air.
(g) Read the value displayed on the Techstream.
Standard:
-40°C (-40°F)
(h) Reconnect the mass air flow meter connector.
NG -- REPLACE ECM Removal
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)