engine coolant NISSAN 350Z 2007 Z33 Engine Control Service Manual

DTC P0127 IAT SENSOR
EC-243
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Revision: 2006 November2007 350Z
DTC P0127 IAT SENSORPFP:22630
Component DescriptionNBS00068
The intake air temperature sensor (1) is built into mass air flow sen-
sor. The sensor detects intake air temperature and transmits a signal
to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: This data is reference values and is measured between ECM terminal 67 [Intake
air temperature sensor (bank 1)] and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS00069
DTC Confirmation ProcedureNBS0006A
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.
CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road
test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Wait until engine coolant temperature is less than 90°C (194°F)
a. Turn ignition switch ON.
b. Select “DATA MONITOR” mode with CONSULT-III.
c. Check the engine coolant temperature.
d. If the engine coolant temperature is not less than 90°C (194°F), turn ignition switch OFF and cool down
engine.
NOTE:
Perform the following steps before engine coolant temperature is above 90°C (194°F).
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
PBIA9559J
Intake air temperature
°C (°F)Voltage* V Resistance kΩ
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0127
0127Intake air temperature
too highRationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signal
from engine coolant temperature sensor.

Harness or connectors
(The sensor circuit is open or shorted)

Intake air temperature sensor

EC-246
DTC P0128 THERMOSTAT FUNCTION
Revision: 2006 November2007 350Z
DTC P0128 THERMOSTAT FUNCTIONPFP:21200
On Board Diagnosis LogicNBS0006E
Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long
enough.
This is due to a leak in the seal or the thermostat stuck open.
DTC Confirmation ProcedureNBS0006F
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.
CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:

For best results, perform at ambient temperature of –10°C (14°F) or higher.

For best results, perform at engine coolant temperature of –10°C (14°F) to 68°C (154°F).
WITH CONSULT-III
1. Replace thermostat with new one. Refer to CO-26, "WATER INLET AND THERMOSTAT ASSEMBLY" .
Use only a genuine NISSAN thermostat as a replacement. If an incorrect thermostat is used, the MIL may
come on.
2. Turn ignition switch ON.
3. Select “COOLAN TEMP/S” in “DATA MONITOR” mode with CONSULT-III.
4. Check the indication of “COOLAN TEMP/S”.
If it is below 68°C (154°F), go to following step.
If it is above 68°C (154°F), cool down the engine to less than 60°C (140°F), then go to next step.
5. Drive vehicle for 10 consecutive minutes under the following conditions.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-246, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS0006G
1. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-247, "
Component Inspection" .
OK or NG
OK >>INSPECTION END
NG >> Replace engine coolant temperature sensor.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0128
0128Thermostat functionThe engine coolant temperature does not
reach to specified temperature even though
the engine has run long enough.

Thermostat

Leakage from sealing portion of thermo-
stat

Engine coolant temperature sensor
VHCL SPEED SE 80 - 120 km/h (50 - 75 MPH)

DTC P0128 THERMOSTAT FUNCTION
EC-247
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Revision: 2006 November2007 350Z
Component InspectionNBS0006H
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.

2. If NG, replace engine coolant temperature sensor.
Removal and InstallationNBS0006I
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-28, "WATER OUTLET AND WATER PIPING" .
PBIB2005E
Engine coolant
temperature°C (°F)Resistance kΩ
20 (68) 2.37 - 2.63
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

EC-290
DTC P0137, P0157 HO2S2
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)
17 PHeated oxygen sensor 2
heater (bank 1)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
76 W/RHeated oxygen sensor 2
(bank 1)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-292
DTC P0137, P0157 HO2S2
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)
33 PU/WHeated oxygen sensor 2
heater (bank 2)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
80 R/YHeated oxygen sensor 2
(bank 2)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-302
DTC P0138, P0158 HO2S2
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)
17 PHeated oxygen sensor 2
heater (bank 1)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
76 W/RHeated oxygen sensor 2
(bank 1)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-304
DTC P0138, P0158 HO2S2
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)
33 PU/WHeated oxygen sensor 2
heater (bank 2)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
80 R/YHeated oxygen sensor 2
(bank 2)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-316
DTC P0139, P0159 HO2S2
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)
17 PHeated oxygen sensor 2
heater (bank 1)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
76 W/RHeated oxygen sensor 2
(bank 1)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-318
DTC P0139, P0159 HO2S2
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)
33 PU/WHeated oxygen sensor 2
heater (bank 2)[Engine is running]

Engine speed: Below 3,600 rpm after the
following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 14V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
80 R/YHeated oxygen sensor 2
(bank 2)[Engine is running]

Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load.0 - 1.0V
84 GSensor ground
(Heated oxygen sensor 2,
Engine coolant temperature
sensor, Engine oil tempera-
ture sensor)[Engine is running]

Warm-up condition

Idle speed0V
PBIB3545E

EC-324
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 November2007 350Z
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS00070
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the air fuel ratio (A/F) sensors 1. The
ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureNBS00071
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 warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Start engine again and le it idle for at least 10 minutes.
6. Check 1st trip DTC.
The 1st trip DTC P0171 or P0174 should be detected at this stage, if a malfunction exists. If so, go to EC-
330, "Diagnostic Procedure" .
NOTE:
If 1st trip DTC is not detected during above procedure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and select “DATA MONITOR” mode with CONSULT-III.
c. Drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 minutes.
Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
Sensor Input signal to ECM ECM function Actuator
Air fuel ratio (A/F) sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection control Fuel injector
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0171
0171
(Bank 1)
Fuel injection system too
lean

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)

Intake air leaks

Air fuel ratio (A/F) sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Lack of fuel

Mass air flow sensor

Incorrect PCV hose connection P0174
0174
(Bank 2)
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature
(T) conditionWhen the freeze frame data shows lower than 70 °C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).