NR Series ENGINE CONTROL SFI SYSTEM P011011 Intake Air Temperature Sensor 1 Bank 1 Circuit Short to Ground
DESCRIPTION
The intake air temperature sensor, mounted on the mass air flow meter sub-assembly, 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 DTC P011011 is stored, 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, and the ignition switch is then turned off.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
|---|---|---|---|---|---|---|
| P011011 | Intake Air Temperature Sensor 1 Bank 1 Circuit Short to Ground | Diagnosis Condition:
·
Ignition switch ON Abnormal condition: ·
The intake air temperature sensor output voltage is less than 0.176 V. Malfunction Time: ·
0.5 seconds or more Trip logic: ·
1 trip detection logic Detection Conditions: ·
Continuous Sensors/components used for detection: ·
Intake air temperature sensor |
·
Short in intake air temperature sensor circuit ·
Mass air flow meter sub-assembly ·
ECM |
Comes on | DTC stored | SAE Code:
P0112 |
- HINT:
-
When this DTC is output, check the intake air temperature in the Data List. Enter the following menus: Powertrain / Engine / Data List / Intake Air Temperature.
DTC No. Intake Air Temperature Malfunction P011011 Higher than 128°C (262°F) Short to ground in THA circuit
-
If the Data List values is normal it may be due to a temporary recovery from the malfunction condition. Check for intermittent problems.
MONITOR DESCRIPTION
When the ignition switch is turned to ON and the output voltage of the intake air temperature sensor is less than 0.176 V for 0.5 seconds or more, the ECM determines that the intake air temperature sensor circuit is malfunctioning and illuminates the MIL and stores a DTC.
MONITOR STRATEGY
| Frequency of Operation | Continuous |
CONFIRMATION DRIVING PATTERN
- HINT:
- ·
After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
·When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON [A].
Turn the GTS on.
Wait 0.5 seconds or more [B].
Enter the following menus: Powertrain / Engine / Trouble Codes [C].
Read the pending DTCs.
- HINT:
- ·
If a pending DTC is output, the system is malfunctioning.
·If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Proceed to the next screen and enter the DTC to be checked.
Check the DTC judgment result.
| GTS Display | Description |
|---|---|
| NORMAL | ·
DTC judgment completed ·
System normal |
| ABNORMAL | ·
DTC judgment completed ·
System abnormal |
| INCOMPLETE | ·
DTC judgment not completed ·
Perform driving pattern after confirming DTC enabling conditions |
- HINT:
- ·
If the judgment result shows NORMAL, the system is normal.
·If the judgment result shows ABNORMAL, the system has a malfunction.
·[A] to [C]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
·When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
- HINT:
-
Read Freeze Frame Data using the GTS. The ECM records vehicle and driving condition information as Freeze Frame Data the moment a DTC is stored. When troubleshooting, Freeze Frame Data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
| *1 | Intake Air Temperature Sensor |
| *2 | ECM |
Disconnect the intake air temperature sensor connector.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / Intake Air Temperature.
- Powertrain > Engine > Data List
-
Tester Display Intake Air Temperature - 50003 372 214
Read the value displayed on the GTS.
- OK:
GTS Display Specified Condition Intake Air Temperature -40°C (-40°F)
- HINT:
-
Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.
- Result:
Proceed to OK NG
OK
NG
Disconnect the intake air temperature sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition C25-4 (THA) or C78-94 (THA) - Body ground and other terminals Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG