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 Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition | Possible cause |
P0506 | 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. |
|
DTC CONFIRMATION PROCEDURE
1.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, performEC-140, "Work Procedure", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected? YES >> Proceed to EC-334, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK INTAKE AIR LEAK
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> Replace ECM. Refer to EC-485, "Removal and Installation".
NISSAN Intelligent Key® (if so equipped)
WARNING
Radio waves could adversely affect
electric medical equipment. Those who
use a pacemaker should contact the
electric medical equipment manufacturer
for the possible influences before
use.
The Intelligent Key transmits radio
waves when the buttons are pr ...
Easy fill tire alert does not activate
Description
The Easy Fill Tire Alert does not function while inflating a tire when the
select lever position is in P-range with
the ignition switch ON. Refer to WT-8, "TIRE PRESSURE MONITORING SYSTEM : Easy
Fill Tire Alert Function".
Diagnosis Procedure
1. LOCATION CHANGE
Move the ...
Diagnosis system (BCM) (without intelligent key system)
Common item
Common item : consult function (bcm - common item)
APPLICATION ITEM
CONSULT performs the following functions via CAN communication with BCM.
Direct Diagnostic Mode
Description
ECU identification
The BCM part number is displayed.
Self Diagnostic Result
...