For California
DTC P0127 IAT SENSOR
Component Description
The intake air temperature sensor is built into mass air flow sensor
(1). The sensor detects intake air temperature and transmits a signal to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to the change in temperature. Electrical resistance of the thermistor decreases in response to the temperature rise.
[Reference data]
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis Logic
DTC Confirmation Procedure
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Wait until engine coolant temperature is less than 96�C (205�F)
a. Turn ignition switch ON.
b. Select "DATA MONITOR" mode with CONSULT-III.
c. Check the engine coolant temperature.
If the engine coolant temperature is not less than 96�C (205�F), turn ignition switch OFF and cool down d.
engine.
- Perform the following steps before engine coolant temperature is above 96�C (205�F).
2. Turn ignition switch ON.
3. Select "DATA MONITOR" mode with CONSULT-III.
4. Start engine.
5. Hold vehicle speed at more than 70 km/h (43 MPH) for 100 consecutive seconds.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to For California.
WITH GST
Follow the procedure "With CONSULT-III" above.
Diagnosis Procedure
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. For California.
Arrow Indicates Vehicle front
- Body ground (1)
OK or NG
OK - GO TO 2.
NG - Repair or replace ground connections.
2.CHECK INTAKE AIR TEMPERATURE SENSOR
For California.
OK or NG
OK - GO TO 3.
NG - Replace mass air flow sensor (with intake air temperature sensor).
3.CHECK INTERMITTENT INCIDENT
For California.
- INSPECTION END
Component Inspection
INTAKE AIR TEMPERATURE SENSOR
1. Check resistance between intake air temperature sensor (1) terminals 5 and 6 under the following conditions.
2. If NG, replace mass air flow sensor (with intake air temperature sensor).
Removal and Installation
MASS AIR FLOW SENSOR
Component Removal And Installation.