Nissan Sentra Service Manual: P0506 ISC System
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.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
If the target idle speed is out of the specified value, performEC-140, "Work Procedure", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
- Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.
- Always perform the test at a temperature above −10В°C (14В°F).
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
- Start engine and warm it up to normal operating temperature.
- Turn ignition switch OFF and wait at least 10 seconds.
- Start engine and run it for at least 1 minute at idle speed.
- Check 1st trip DTC.
Is 1st trip DTC detected? YES >> Proceed to EC-334, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK INTAKE AIR LEAK
- Start engine and let it idle.
- Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> Replace ECM. Refer to EC-485, "Removal and Installation".
P0500 VSS
EXCEPT FOR M/T MODELS
EXCEPT FOR M/T MODELS : Description
ECM receives vehicle speed signals from two different paths via CAN
communication line: One is from the
ABS actuator and electric unit (c ...
P0507 ISC System
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 ac ...
Other materials:
Low tire pressure warning lamp does not turn oFF
Low Tire Pressure Warning Lamp Stays On When Ignition Switch Is Turned On
DIAGNOSTIC PROCEDURE
1.INSPECT BCM CONNECTOR
Turn ignition switch OFF.
Disconnect BCM connectors.
Check terminals for damage or loose connections.
Is the inspection result normal?
YES >> GO TO 2.
NO > ...
B0091 Front side air bag satellite sensor LH
Description
DTC B0091 FRONT SATELLITE SENSOR LH
The front side air bag satellite sensor LH is wired to the air bag diagnosis
sensor unit. The air bag diagnosis
sensor unit will monitor the front side air bag satellite sensor LH for internal
failures and its circuits for communication
errors. ...
Component parts
Component Parts Location
Driver air bag module
Front passenger air bag off indicator
Front passenger air bag module
Front LH side air bag module
(RH similar)
LH side curtain air bag module
(view with headliner removed)
(RH similar)
Front LH seatbelt pre-tensioner
(view wit ...
