2007 NISSAN 350Z ignition

EC-600
DTC P1421 COLD START CONTROL
Revision: 2006 November2007 350Z
DTC P1421 COLD START CONTROLPFP:23710
DescriptionNBS006TX
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicNBS006TY
DTC Confirmation ProcedureNBS006TZ
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 DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that the “COOLAN TEMP/S” indication is between 4°C (39°F) and 36°C (97°F).
If “COOLAN TEMP/S” indication is within the specified value, go to the following step.
If “COOLANT TEMP/S” indication is out of the specified value, cool engine down or warm engine up and
go to step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-600, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS006U0
1. PERFORM IDLE AIR VOLUME LEARNING
Perform EC-77, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 2.
No >> Follow the instruction of Idle Air Volume Learning.
2. CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.

Crushed intake air passage

Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421Cold start emission reduction
strategy monitoringECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.

Lack of intake air volume

Fuel injection system

ECM

DTC P1421 COLD START CONTROL
EC-601
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Revision: 2006 November2007 350Z
3. CHECK FUEL INJECTION SYSTEM FUNCTION
Perform EC-324, "
DTC Confirmation Procedure" for DTC P0171.
OK or NG
OK >> GO TO 4.
NG >> Go to EC-330, "
Diagnostic Procedure" for DTC P0171.
4. PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS” mode with CONSULT-III.
3. Touch “ERASE”.
4.Perform DTC Confirmation Procedure.
See EC-600, "
DTC Confirmation Procedure" .
5. Is the 1st trip DTC P1421 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3.Perform DTC Confirmation Procedure.
See EC-600, "
DTC Confirmation Procedure" .
4. Is the 1st trip DTC P1421 displayed again?
Ye s o r N o
Ye s > > G O T O 5 .
No >>INSPECTION END
5. REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to BL-152, "
ECM Re-communicating Function" .
3. Perform EC-76, "
VIN Registration" .
4. Perform EC-76, "
Exhaust Valve Timing Control Learning" .
5. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-77, "
Throttle Valve Closed Position Learning" .
7. Perform EC-77, "
Idle Air Volume Learning" .
>>INSPECTION END

EC-602
DTC P1564 ASCD STEERING SWITCH
Revision: 2006 November2007 350Z
DTC P1564 ASCD STEERING SWITCHPFP:25551
Component DescriptionNBS000FT
ASCD steering switch has variant values of electrical resistance for each button. ECM reads voltage variation
of switch, and determines which button is operated.
Refer to EC-30, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for the ASCD function.
CONSULT-III Reference Value in Data Monitor ModeNBS000FU
Specification data are reference values.
On Board Diagnosis LogicNBS000FV

This self-diagnosis has the one trip detection logic.

The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1564 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-512, "
DTC P0605 ECM".
1. ASCD steering switch 2. RESUME/ACCELERATE switch 3. SET/COAST switch
4. CANCEL switch 5. MAIN switch
PBIB3497E
MONITOR ITEM CONDITION SPECIFICATION
MAIN SW

Ignition switch: ONMAIN switch: Pressed ON
MAIN switch: Released OFF
CANCEL SW

Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW

Ignition switch: ONRESUME/ACCELERATE switch:
PressedON
RESUME/ACCELERATE switch:
ReleasedOFF
SET SW

Ignition switch: ONSET/COAST switch: Pressed ON
SET/COAST switch: Released OFF
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P1564
1564ASCD steering
switch

An excessively high voltage signal from the ASCD
steering switch is sent to ECM.

ECM detects that input signal from the ASCD
steering switch is out of the specified range.

ECM detects that the ASCD steering switch is
stuck ON.

Harness or connectors
(The switch circuit is open or shorted.)

ASCD steering switch

ECM

DTC P1564 ASCD STEERING SWITCH
EC-603
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EC
Revision: 2006 November2007 350Z
DTC Confirmation ProcedureNBS000FW
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. Turn ignition switch ON and wait at least 10 seconds.
2. Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
3. Press CANCEL switch for at least 10 seconds, then release it and wait at least 10 seconds.
4. Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 sec-
onds.
5. Press SET/COAST switch for at least 10 seconds, then release it and wait at least 10 seconds.
6. Check DTC.
7. If DTC is detected, go to EC-606, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.

DTC P1564 ASCD STEERING SWITCH
EC-605
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EC
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)
101 G/Y ASCD steering switch[Ignition switch: ON]

ASCD steering switch: OFF4V
[Ignition switch: ON]

MAIN switch: Pressed0V
[Ignition switch: ON]

CANCEL switch: Pressed1V
[Ignition switch: ON]

RESUME/ACCELERATE switch: Pressed3V
[Ignition switch: ON]

SET/COAST switch: Pressed2V
108 B/YSensor ground
(ASCD steering switch)[Engine is running]

Warm-up condition

Idle speed0V

EC-606
DTC P1564 ASCD STEERING SWITCH
Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS000FY
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

DTC P1564 ASCD STEERING SWITCH
EC-607
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Revision: 2006 November2007 350Z
2. CHECK ASCD STEERING SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “MAIN SW”, “RESUME/ACC SW”, “SET SW” and “CANCEL SW” in “DATA MONITOR” mode with
CONSULT-III.
3. Check each item indication under the following conditions.
Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 101 and ground with
pressing each button.
OK or NG
OK >> GO TO 8.
NG >> GO TO 3.
3. CHECK ASCD STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect combination switch harness connector M203.
4. Check harness continuity between combination switch terminal 15 and ECM terminal 108.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
Switch Monitor item Condition Indication
MAIN switch MAIN SWPressed ON
Released OFF
CANCEL switch CANCEL SWPressed ON
Released OFF
RESUME/ACCELERATE switch RESUME/ACC SWPressed ON
Released OFF
SET/COAST switch SET SWPressed ON
Released OFF
Switch Condition Voltage [V]
MAIN switchPressed Approx. 0
Released Approx. 4
CANCEL switchPressed Approx. 1
Released Approx. 4
RESUME/ACCELERATE
switchPressed Approx. 3
Released Approx. 4
SET/COAST switchPressed Approx. 2
Released Approx. 4
PBIB1537E
Continuity should exist.

EC-610
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
DTC P1572 ASCD BRAKE SWITCHPFP:25320
Component DescriptionNBS000G0
When the brake pedal is depressed, ASCD brake switch is turned
OFF and stop lamp switch is turned ON. ECM detects the state of
the brake pedal by this input of two kinds (ON/OFF signal).
Refer to EC-30, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)"
for the ASCD function.
CONSULT-III Reference Value in Data Monitor ModeNBS000G1
Specification data are reference values.
On Board Diagnosis LogicNBS000G2

This self-diagnosis has the one trip detection logic.

The MIL will not light up for this self-diagnosis.
NOTE:

If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-512, "
DTC P0605 ECM".

This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two
consecutive trips, DTC is not stored in ECM memory.
PBIB1282E
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW1
(ASCD brake switch)

Ignition switch: ON

Brake pedal: Fully released (A/T)

Brake pedal and clutch pedal: Fully
released (M/T)ON

Brake pedal: Slightly depressed (A/T)

Brake pedal and/or clutch pedal:
Slightly depressed (M/T)OFF
BRAKE SW2
(Stop lamp switch)

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P1572
1572ASCD brake switchA)When the vehicle speed is above 30km/h
(19 MPH), ON signals from the stop lamp
switch and the ASCD brake switch are sent
to ECM at the same time.

Harness or connectors
(The stop lamp switch circuit is shorted.)

Harness or connectors
(The ASCD brake switch circuit is shorted.)

Harness or connectors
(The ASCD clutch switch circuit is shorted.)
(M/T models)

Stop lamp switch

ASCD brake switch

ASCD clutch switch (M/T models)

Incorrect stop lamp switch installation

Incorrect ASCD brake switch installation

Incorrect ASCD clutch switch installation
(M/T models)

ECM B)ASCD brake switch signal is not sent to
ECM for extremely long time while the vehi-
cle is driving