Infiniti Q45. Manual - part 459

DTC P0500 VSS

EC-475

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EC

Overall Function Check

NBS001YL

Use this procedure to check the overall function of the vehicle speed sensor circuit. During this check, a 1st
trip DTC might not be confirmed.

 WITH GST

1.

Lift up drive wheels.

2.

Start engine.

3.

Read vehicle speed sensor signal in “Service $01” with GST.
The vehicle speed sensor on GST should be able to exceed 10 km/h (6 MPH) when rotating wheels with
suitable gear position.

4.

If NG, go to 

EC-475, "Diagnostic Procedure"

 .

Diagnostic Procedure

NBS001YM

1. 

CHECK DTC WITH VDC/TCS/ABS CONTROL UNIT

Refer to 

BRC-10, "TROUBLE DIAGNOSIS"

 .

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace.

2. 

CHECK COMBINATION METER

Check combination meter function.
Refer to 

DI-7, "COMBINATION METERS"

 .

>> INSPECTION END

EC-476

DTC P0506 ISC SYSTEM

DTC P0506 ISC SYSTEM

PFP:23781

Description

NBS001YN

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 Logic

NBS001YO

DTC Confirmation Procedure

NBS001YP

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-78, "Idle Air Volume Learning"

 ,

before conducting DTC Confirmation Procedure. For the target idle speed, refer to the 

EC-759,

"SERVICE 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-II

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.

Turn ignition switch ON again and select “DATA MONITOR”
mode with CONSULT-II.

5.

Start engine and run it for at least 1 minute at idle speed.

6.

If 1st trip DTC is detected, go to 

EC-477, "Diagnostic Procedure"

.

 WITH GST

Follow the procedure WITH CONSULT-II above.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0506
0506

Idle speed control system 
RPM lower than expected

The idle speed is less than the target idle 
speed by 100 rpm or more.

●

Electric throttle control actuator

●

Intake air leak

SEF174Y

DTC P0506 ISC SYSTEM

EC-477

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Diagnostic Procedure

NBS001YQ

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.

2. 

REPLACE ECM

1.

Stop engine.

2.

Replace ECM.

3.

Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to

BL-202, "ECM Re-Communicating Function"

 .

4.

Perform 

EC-77, "VIN Registration"

 .

5.

Perform 

EC-77, "Accelerator Pedal Released Position Learning"

 .

6.

Perform 

EC-78, "Throttle Valve Closed Position Learning"

 .

7.

Perform 

EC-78, "Idle Air Volume Learning"

 .

>> INSPECTION END

EC-478

DTC P0507 ISC SYSTEM

DTC P0507 ISC SYSTEM

PFP:23781

Description

NBS001YR

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 Logic

NBS001YS

DTC Confirmation Procedure

NBS001YT

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-78, "Idle Air Volume Learning"

 ,

before conducting DTC Confirmation Procedure. For the target idle speed, refer to the 

EC-759,

"SERVICE 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-II

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.

Turn ignition switch ON again and select “DATA MONITOR”
mode with CONSULT-II.

5.

Start engine and run it for at least 1 minute at idle speed.

6.

If 1st trip DTC is detected, go to 

EC-479, "Diagnostic Procedure"

.

 WITH GST

Follow the procedure WITH CONSULT-II above.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0507
0507

Idle speed control system 
RPM higher than expected

The idle speed is more than the target idle 
speed by 200 rpm or more.

●

Electric throttle control actuator

●

Intake air leak

●

PCV system

SEF174Y