Description
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions, such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan operation, etc.).
DTC Description
DTC DETECTION LOGIC
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
P050 | ISC SYSTEM (Idle air control system RPM lower than expected) | The idle speed is less than the target idle speed by 100 rpm or more. |
POSSIBLE CAUSE
FAIL-SAFE
Not applicable
DTC CONFIRMATION PROCEDURE
1.CHECK DTC PRIORITY
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
Is applicable DTC detected? YES >> Perform diagnosis of applicable. Refer to EC-93, "DTC Index".
NO >> GO TO 2.
2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
If the target idle speed is out of the specified value, perform EC-141, "Work Procedure", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
>> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected? YES >> Proceed to EC-353, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK DTC PRIORITY
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
Is applicable DTC detected? YES >> Perform diagnosis of applicable. Refer to EC-93, "DTC Index".
NO >> GO TO 2.
2.CHECK INTAKE AIR LEAK
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> Replace ECM. Refer to EC-499, "Removal and Installation".
Forward-facing child restraint installation
using LATCH
For additional information, refer to all Warnings
and Cautions in the “Child Safety” and “Child
Restraints” sections before installing a child restraint.
NISSAN does not recommend the use of the
lower anchors if the combined weight of the child
and the child restraint exceeds 65 lbs ( ...
Flat towing for All–Wheel drive vehicle
(if so equipped)
Towing your vehicle with all four wheels on the
ground is sometimes called flat towing. This
method is sometimes used when towing a vehicle
behind a recreational vehicle, such as a motor
home.
CAUTION
Failure to follow these guidelines can
result in severe transmission dama ...
Active ride control
This system senses upper body motion (based
on wheel speed information) and controls engine
torque and four wheel brake pressure. This will
enhance ride comfort in effort to restrain uncomfortable
upper body movement when passing
over undulated road surfaces . This system
comes into effect abo ...