2007 NISSAN 350Z battery

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 P1572 ASCD BRAKE SWITCH
EC-613
C
D
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F
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MA
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)
122 P/L Stop lamp switch[Ignition switch: OFF]

Brake pedal: Fully released0V
[Ignition switch: OFF]

Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
126 L/OR ASCD brake switch[Ignition switch: ON]

Brake pedal: Slightly depressed0V
[Ignition switch: ON]

Brake pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V)

DTC P1572 ASCD BRAKE SWITCH
EC-615
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MA
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.
Diagnostic ProcedureNBS000G5
A/T MODELS
1. CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 126 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
122 P/L Stop lamp switch[Ignition switch: OFF]

Brake pedal: Fully released0V
[Ignition switch: OFF]

Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
126 L/OR ASCD brake switch[Ignition switch: ON]

Brake pedal and/or clutch pedal: Slightly
depressed0V
[Ignition switch: ON]

Brake pedal and clutch pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V)
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
PBIB3577E

EC-616
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
2. CHECK OVERALL FUNCTION-II
With CONSULT-III
1. Select “BRAKE SW2” in “DATA MONITOR” mode with CONSULT-III.
2. Check “BRAKE SW2” indication under the following conditions.
Without CONSULT-III
Check voltage between ECM terminal 122 and ground under the following conditions.
OK or NG
OK >> GO TO 13.
NG >> GO TO 8.
3. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and
ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB3578E
PBIB1089E
Voltage: Battery voltage
PBIB0857E

EC-618
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
8. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT-III or tester.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. DETECT MALFUNCTIONING PART
Check the following.

Fuse block (J/B) connector E101

10A fuse

Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
10. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 122 and stop lamp switch terminal 4.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E108, M15

Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB1089E
Voltage: Battery voltage
PBIB2309E
Continuity should exist.

DTC P1572 ASCD BRAKE SWITCH
EC-619
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EC
Revision: 2006 November2007 350Z
12. CHECK STOP LAMP SWITCH
Refer to EC-624, "
Component Inspection"
OK or NG
OK >> GO TO 13.
NG >> Replace stop lamp switch.
13. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
M/T MODELS
1. CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 126 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
CONDITION INDICATION
Brake pedal and/or clutch pedal: Slightly depressed OFF
Brake pedal and clutch pedal: Fully released ON
CONDITION VOLTAGE
Brake pedal and/or clutch pedal: Slightly depressed Approximately 0V
Brake pedal and clutch pedal: Fully released Battery voltage
PBIB3577E

EC-620
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
2. CHECK OVERALL FUNCTION-II
With CONSULT-III
1. Select “BRAKE SW2” in “DATA MONITOR” mode with CONSULT-III.
2. Check “BRAKE SW2” indication under the following conditions.
Without CONSULT-III
Check voltage between ECM terminal 122 and ground under the fol-
lowing conditions.
OK or NG
OK >> GO TO 16.
NG >> GO TO 11.
3. CHECK ASCD BRAKE SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD clutch switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD clutch switch terminal 1 and
ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 4.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB3578E
PBIB1282E
Voltage: Battery voltage
PBIB0799E

DTC P1572 ASCD BRAKE SWITCH
EC-621
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MA
EC
Revision: 2006 November2007 350Z
4. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and
ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Fuse block (J/B) connector E101

10A fuse

Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ASCD brake switch terminal 2 and ASCD clutch switch terminal 1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK ASCD BRAKE SWITCH
Refer to EC-624, "
Component Inspection"
OK or NG
OK >> GO TO 16.
NG >> Replace ASCD brake switch.
PBIB1282E
Voltage: Battery voltage
PBIB0857E
Continuity should exist.