Page 497 of 720

DTC P0500 VSS
EC-497
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 November2007 350Z
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-497, "
Diagnostic Procedure" .
Overall Function CheckNBS000AK
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-497, "
Diagnostic Procedure" .
Diagnostic ProcedureNBS000AL
1. CHECK DTC WITH “VDC/TCS/ABS CONTROL UNIT (WITH VDC MODELS)” OR “ABS ACTUATOR
AND ELECTRIC UNIT (CONTROL UNIT) (WITHOUT VDC MODELS)”
Refer to BRC-82, "
TROUBLE DIAGNOSIS" (with VDC models) or refer to BRC-42, "TROUBLE DIAGNOSIS"
(without VDC models).
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK DTC WITH UNIFIED METER AND A/C AMP.
Refer to DI-4, "
COMBINATION METERS" .
>>INSPECTION END
B/FUEL SCHDL5.0 - 31.8 msec (A/T)
5.0 - 31.8 msec (M/T)
Shift leverExcept P or N position (A/T)
Neutral position (M/T)
PW/ST SIGNAL OFF
Page 498 of 720

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
Page 500 of 720

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
Page 501 of 720
DTC P0507 ISC SYSTEM
EC-501
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 November2007 350Z
2. 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 3.
NG >> Discover air leak location and repair.
3. REPLACE ECM
1. Stop engine.
2. Replace ECM.
3. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to BL-152, "
ECM Re-communicating Function" .
4. Perform EC-76, "
VIN Registration" .
5. Perform EC-76, "
Exhaust Valve Timing Control Learning" .
6. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
7. Perform EC-77, "
Throttle Valve Closed Position Learning" .
8. Perform EC-77, "
Idle Air Volume Learning" .
>>INSPECTION END
Page 502 of 720

EC-502
DTC P0550 PSP SENSOR
Revision: 2006 November2007 350Z
DTC P0550 PSP SENSORPFP:49763
Component DescriptionNBS000AU
Power steering pressure (PSP) sensor (1) is installed to the power
steering high-pressure tube and detects a power steering load. This
sensor is a potentiometer which transforms the power steering load
into output voltage, and emits the voltage signal to the ECM. The
ECM controls the electric throttle control actuator and adjusts the
throttle valve opening angle to increase the engine speed and
adjusts the idle speed for the increased load.
CONSULT-III Reference Value in Data Monitor ModeNBS000AV
Specification data are reference values.
On Board Diagnosis LogicNBS000AW
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P0550 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-514, "
DTC P0643 SENSOR POWER SUPPLY" .
DTC Confirmation ProcedureNBS000AX
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.
WITH CONSULT-III
1. Start engine and let it idle for at least 5 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-505, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
2 : Alternator
: Vehicle front
PBIB3511E
MONITOR ITEM CONDITION SPECIFICATION
PW/ST SIGNAL
Engine: After warming up, idle
the engineSteering wheel: Not being turned OFF
Steering wheel: Being turned ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0550
0550Power steering pres-
sure sensor circuitAn excessively low or high voltage from the
sensor is sent to ECM.
Harness or connectors
(The sensor circuit is open or shorted)
Power steering pressure sensor
Page 503 of 720
DTC P0550 PSP SENSOR
EC-503
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 November2007 350Z
Wiring DiagramNBS000AY
TBWT1651E
Page 504 of 720
EC-504
DTC P0550 PSP SENSOR
Revision: 2006 November2007 350Z
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
60 R/LSensor power supply
[Camshaft position sensor
(PHASE) (bank 1), Exhaust
valve timing control position
sensor (bank 1), Power
steering pressure sensor][Ignition switch: ON]5V
87 YPower steering pressure
sensor[Engine is running]
Steering wheel: Being turned0.5 - 4.5V
[Engine is running]
Steering wheel: Not being turned0.4 - 0.8V
96 P/LSensor ground
[Camshaft position sensor
(PHASE) (bank 1), Power
steering pressure sensor][Engine is running]
Warm-up condition
Idle speed0V
Page 505 of 720
DTC P0550 PSP SENSOR
EC-505
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS000AZ
1. CHECK GROUND CONNECTIONS
Models with VDC system, navigation system or telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
Models without VDC system, navigation system and telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
1. Body ground E17 2. Body ground E43 3. Body ground B102
:Vehicle front
1. Body ground E17 2. Body ground E43 3. Body ground F152
(Passenger side view with dash side
finisher removed)
:Vehicle front
PBIB3560E
PBIB3561E