engine coolant NISSAN 350Z 2007 Z33 Engine Control Owner's Guide

EC-160
DTC P0014 P0024 EVT CONTROL
Revision: 2006 November2007 350Z
DTC P0014 P0024 EVT CONTROLPFP:23795
DescriptionNBS0004C
SYSTEM DESCRIPTION
*: This signal is sent to the ECM through CAN Communication line
This mechanism magnetically controls cam phases continuously with the fixed operating angle of the exhaust
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the exhaust valve timing control magnet
retarder depending on driving status. This makes it possible to control the shut/open timing of the exhaust
valve to increase engine torque and output in a range of high engine speed.
CONSULT-III Reference Value in Data Monitor ModeNBS0004D
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed and piston position
Exhaust valve
timing controlExhaust valve timing con-
trol magnet retarder Camshaft position sensor (PHASE)
Engine coolant temperature sensor Engine coolant temperature
Exhaust valve timing control position sensor Exhaust valve timing signal
Wheel sensor Vehicle speed*
PBIB2765E
MONITOR ITEM CONDITION SPECIFICATION
EXH/V TIM B1
EXH/V TIM B2

Engine: After warming up

Shift lever: Neutral

Air conditioner switch: OFF

No loadIdle−5° - 5°CA
Around 2,500 rpm while the engine
speed is risingApprox. 0° - 30°CA
EX VTC DTY B1
EX VTC DTY B2

Engine: After warming up

Shift lever: Neutral

Air conditioner switch: OFF

No loadIdle 0% - 2%
Around 2,500 rpm while the engine
speed is risingApprox. 0% - 70%

DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-173
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Revision: 2006 November2007 350Z
DTC P0037, P0038, P0057, P0058 HO2S2 HEATERPFP:226A0
DescriptionNBS0004J
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 (HO2S2) heater corresponding to the
engine speed, amount of intake air and engine coolant temperature.
OPERATION
CONSULT-III Reference Value in Data Monitor ModeNBS0004K
Specification data are reference values.
On Board Diagnosis LogicNBS0004L
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Engine speed
Heated oxygen sensor 2
(HO2S2) heater controlHeated oxygen sensor 2
(HO2S2) heater Crankshaft position sensor (POS)
Engine coolant temperature sensorEngine coolant tempera-
ture
Mass air flow sensor Amount of intake air
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600OFF
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 loadON
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
HO2S2 HTR (B2)

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 loadON

Engine speed: Above 3,600 rpm OFF
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0037
0037
(Bank 1)
HO2S2 heater
control circuit lowThe current amperage in the HO2S2 heater cir-
cuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the HO2S2 heater.)

Harness or connectors
(The HO2S2 heater circuit is open or
shorted.)

HO2S2 heater P0057
0057
(Bank 2)
P0038
0038
(Bank 1)
HO2S2 heater
control circuit highThe current amperage in the HO2S2 heater cir-
cuit is out of the normal range.
(An excessively high voltage signal is sent to
ECM through the HO2S2 heater.)

Harness or connectors
(The HO2S2 heater circuit is shorted.)

HO2S2 heater P0058
0058
(Bank 2)

EC-176
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
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-178
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
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

DTC P0117, P0118 ECT SENSOR
EC-223
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Revision: 2006 November2007 350Z
DTC P0117, P0118 ECT SENSORPFP:22630
Component DescriptionNBS0005N
The engine coolant temperature (ECT) sensor is used to detect the
engine coolant temperature. The sensor modifies a voltage signal
from the ECM. The modified signal returns to the ECM as the engine
coolant temperature input. The sensor uses a thermistor which is
sensitive to the change in temperature. The electrical resistance of
the thermistor decreases as temperature increases.

*: This data is reference values and is measured between ECM terminal 71 (Engine
coolant temperature sensor) 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.
On Board Diagnosis LogicNBS0005O
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
SEF594K
Engine coolant temperature
°C (°F)Voltage* V Resistance kΩ
−10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.37 - 2.63
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P0117
0117Engine coolant tem-
perature sensor cir-
cuit low inputAn excessively low voltage from the sensor is
sent to ECM.

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

Engine coolant temperature sensor
P0118
0118Engine coolant tem-
perature sensor cir-
cuit high inputAn excessively high voltage from the sensor is
sent to ECM.
Detected items Engine operating condition in fail-safe mode
Engine coolant temper-
ature sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning ignition switch ON
or START.
CONSULT-III displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON or START 40°C (104°F)
More than approx. 4 minutes after ignition ON or
START80°C (176°F)
Except as shown above40 - 80°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates
while engine is running.

DTC P0117, P0118 ECT SENSOR
EC-227
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Revision: 2006 November2007 350Z
2. CHECK ENGINE COOLANT TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine coolant temperature sensor harness connec-
tor (1).
2. Turn ignition switch ON.
3. Check voltage between engine coolant temperature sensor ter-
minal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3. CHECK ENGINE COOLANT TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ENGINE COOLANT TEMPERATURE sensor terminal 2 and ECM ter-
minal 84.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-228, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace engine coolant temperature sensor.
5. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
: Vehicle front
PBIB3503E
Voltage: Approximately 5V
PBIB0080E
Continuity should exist.

EC-228
DTC P0117, P0118 ECT SENSOR
Revision: 2006 November2007 350Z
Component InspectionNBS0005S
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 InstallationNBS0005T
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

DTC P0125 ECT SENSOR
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Revision: 2006 November2007 350Z
DTC P0125 ECT SENSORPFP:22630
Component DescriptionNBS00062
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.

*: This data is reference values and is measured between ECM terminal 71 (Engine
coolant temperature sensor) 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.
On Board Diagnosis LogicNBS00063
NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118.
Refer to EC-223, "
DTC P0117, P0118 ECT SENSOR" .
SEF594K
Engine coolant
temperature°C (°F)Voltage* V Resistance kΩ
−10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.37 - 2.63
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0125
0125Insufficient engine cool-
ant temperature for
closed loop fuel control

Voltage sent to ECM from the sensor is not
practical, even when some time has passed
after starting the engine.

Engine coolant temperature is insufficient for
closed loop fuel control.

Harness or connectors
(High resistance in the circuit)

Engine coolant temperature sensor

Thermostat

DTC P0125 ECT SENSOR
EC-241
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Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS00065
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.
2. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-242, "
Component Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Replace engine coolant temperature sensor.
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

EC-242
DTC P0125 ECT SENSOR
Revision: 2006 November2007 350Z
3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace thermostat. Refer to CO-26, "
WATER INLET AND THERMOSTAT ASSEMBLY"
.
4. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Refer to EC-225, "
Wiring Diagram" .
>>INSPECTION END
Component InspectionNBS00066
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 InstallationNBS00067
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