EC-498
DTC P0506 ISC SYSTEM
Revision: 2006 November2007 350Z
DTC P0506 ISC SYSTEMPFP:23781
DescriptionNBS000AM
NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
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.).
On Board Diagnosis LogicNBS000AN
DTC Confirmation ProcedureNBS000AO
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.
If the target idle speed is out of the specified value, perform EC-77, "Idle Air Volume Learning" ,
before conducting DTC Confirmation Procedure. For the target idle speed, refer to EC-718, "
SER-
VICE DATA AND SPECIFICATIONS (SDS)" .
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above −10°C (14°F).
WITH CONSULT-III
1. Open engine hood.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Restart engine and run it for at least 1 minute at idle speed.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to EC-498, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS000AP
1. CHECK INTAKE AIR LEAK
1. Start engine and let it idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 2.
NG >> Discover air leak location and repair.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0506
0506Idle speed control sys-
tem RPM lower than
expectedThe idle speed is less than the target idle
speed by 100 rpm or more.
Electric throttle control actuator
Intake air leak
EC-500
DTC P0507 ISC SYSTEM
Revision: 2006 November2007 350Z
DTC P0507 ISC SYSTEMPFP:23781
DescriptionNBS000AQ
NOTE:
If DTC P0507 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
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.).
On Board Diagnosis LogicNBS000AR
DTC Confirmation ProcedureNBS000AS
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.
If the target idle speed is out of the specified value, perform EC-77, "Idle Air Volume Learning" ,
before conducting DTC Confirmation Procedure. For the target idle speed, refer to EC-718, "
SER-
VICE DATA AND SPECIFICATIONS (SDS)" .
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above −10°C (14°F).
WITH CONSULT-III
1. Open engine hood.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Restart engine and run it for at least 1 minute at idle speed.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to EC-500, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS000AT
1. CHECK PCV HOSE CONNECTION
Confirm that PCV hose is connected correctly.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0507
0507Idle speed control sys-
tem RPM higher than
expectedThe idle speed is more than the target idle
speed by 200 rpm or more.
Electric throttle control actuator
Intake air leak
PCV system
