Nissan Sentra Service Manual: P0127 IATSensor
DTC Logic
DTC DETECTION LOGIC
| DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition | Possible cause |
| P0127 | IAT SENSOR-B1 (Intake air temperature too high) | Rationally incorrect voltage from the sensor is sent to ECM, compared with the voltage signal from engine coolant temperature sensor. |
|
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT
- Wait until engine coolant temperature is less than 96В°C (205В°F)
- Turn ignition switch ON.
- Select “DATA MONITOR” mode of “ENGINE” using CONSULT.
- Check the engine coolant temperature.
- If the engine coolant temperature is not less than 96В°C (205В°F), turn ignition switch OFF and cool down engine.
NOTE:
Perform the following steps before engine coolant temperature is above 96В°C (205В°F).
- Turn ignition switch ON.
- Select “DATA MONITOR” mode of “ENGINE” using CONSULT
- Start engine
- Hold vehicle speed at more than 70 km/h (43 MPH) for 100 consecutive seconds.
CAUTION:
Always drive vehicle at a safe speed.
- Check 1st trip DTC.
With GST
Follow the procedure “With CONSULT” above.
Is 1st trip DTC detected? YES >> Proceed to EC-205, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK INTAKE AIR TEMPERATURE SENSOR
Check the intake air temperature sensor. Refer to EC-206, "Component Inspection".
Is the inspection result normal? YES >> Check intermittent incident. Refer to GI-39, "Intermittent Incident".
NO >> Replace mass air flow sensor (with intake air temperature sensor). Refer to EM-25, "Exploded View".
Component Inspection
1.CHECK INTAKE AIR TEMPERATURE SENSOR
- Turn ignition switch OFF.
- Disconnect mass air flow sensor harness connector and reconnect it again.
- Turn ignition switch ON.
- Select “DATA MONITOR” mode with CONSULT.
- Check that the indicated value of “INT/A TEMP SEN” is almost the same as intake air temperature.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace mass air flow sensor (with intake air temperature sensor). Refer to EM-25, "Exploded View".
P0125 ECT Sensor
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0125 is displayed with P0116, first perform the trouble
diagnosis for DTC P0116. Refer to EC-
196, "DTC Logic".
If DTC P0125 is displ ...
P0128 Thermostat function
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0128 is displayed with DTC P0300, P0301, P0302, P0303 or P0304,
first perform the trouble
diagnosis for P0300, P0301, P0302, P0303 or P0304. Refer to ...
Other materials:
Parking brake switch signal circuit
Component function check
1.Check parking brake switch operation
Check that brake warning lamp in combination meter turns on/off when parking
brake is actuated.
Is the inspection result normal?
Yes >> inspection end.
No >> proceed to diagnosis procedure. Refer to mwi-60, " ...
Dtc/circuit diagnosis
U1000 can comm circuit
Description
Refer to lan-7, "can communication system : system description".
DTC Logic
Dtc detection logic
Note:
U1000 can be set if a module harness was disconnected and reconnected,
perhaps during a repair. Confirm
that there are actual can diagnostic sym ...
Diagnosis system (combination meter)
Consult function (meter/m&a)
Application items
Consult can perform the following diagnosis modes via can communication and
the combination meter.
Self diag result
Refer to mwi-26, "dtc index".
Data monitor
Display item list
Note:
Some items are not available accor ...
