2005 INFINITI FX35 Coolant sensor

EC-826
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-707, "INDEX FOR DTC" .)
Freeze Frame Data and 1st Trip Freeze Frame Data
EVAP SYSTEM CLOSE CLOSE THE EVAP CANISTER VENT CONTROL VALVE IN
ORDER TO MAKE EVAP SYSTEM CLOSE UNDER THE
FOLLOWING CONDITIONS.

IGN SW ON

ENGINE NOT RUNNING

AMBIENT TEMPERATURE IS ABOVE 0 °C (32 °F).

NO VACUUM AND NO HIGH PRESSURE IN EVAP SYS-
TEM

FUEL TANK TEMP. IS MORE THAN 0 °C (32 °F).

WITHIN 10 MINUTES AFTER STARTING “EVAP SYS-
TEM CLOSE”

WHEN TRYING TO EXECUTE “EVAP SYSTEM CLOSE”
UNDER THE CONDITION EXCEPT ABOVE, CONSULT-
II WILL DISCONTINUE IT AND DISPLAY APPROPRI-
ATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-II MAY DISPLAY
“BATTERY VOLTAGE IS LOW. CHARGE BATTERY”,
EVEN IN USING CHARGED BATTERY. When detecting EVAP vapor leak
point of EVAP system
VIN REGISTRATION

IN THIS MODE VIN IS REGISTERED IN ECM When registering VIN in ECM
TARGET IDLE RPM ADJ*

IDLE CONDITION When setting target idle speed
TARGET IGN TIM ADJ*

IDLE CONDITION When adjusting target ignition tim- ing
WORK ITEM CONDITION USAGE
Freeze frame data
item* Description
DIAG TROUBLE
CODE
[PXXXX]

The engine control component part/control system has a trouble code, it is displayed as PXXXX. (Refer to
EC-707, "
INDEX FOR DTC" .)
FUEL SYS-B1

“Fuel injection system status” at the moment a malfunction is detected is displayed.

One mode in the following is displayed.
Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop
FUEL SYS-B2
CAL/LD VALUE [%]

The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [ °C]
or [ °F]

The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]

“Long-term fuel trim” at the moment a malfunction is detected is displayed.

The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim.
L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]

“Short-term fuel trim” at the moment a malfunction is detected is displayed.

The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule.
S-FUEL TRM-B2 [%]
ENGINE SPEED
[rpm]

The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph]

The vehicle speed at the moment a malfunction is detected is displayed.

TROUBLE DIAGNOSIS EC-827
[VK45DE]
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Revision: 2005 July 2005 FX
*: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
× : Applicable
B/FUEL SCHDL
[msec]

The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE [ °C]
or [ °F]

The intake air temperature at the moment a malfunction is detected is displayed.
Freeze frame data
item* Description
Monitored item
[Unit] ECM
INPUT
SIG-
NALS MAIN
SIG-
NALS Description Remarks
ENG SPEED [rpm] ××

Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position sen-
sor (PHASE).
Accuracy becomes poor if engine speed
drops below the idle rpm.

If the signal is interrupted while the
engine is running, an abnormal value may
be indicated.
MAS A/F SE-B1 [V] ××

The signal voltage of the mass air flow
sensor is displayed.
When the engine is stopped, a certain
value is indicated.
B/FUEL SCHDL
[msec] ×

“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
A/F ALPHA-B1 [%] ×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When the engine is stopped, a certain
value is indicated.

This data also includes the data for the
air-fuel ratio learning control.
A/F ALPHA-B2 [%]
×
COOLAN TEMP/S
[ ° C] or [ °F] ××

The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is displayed.

When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine coolant
temperature determined by the ECM is
displayed.
HO2S1 (B1) [V] ××

The signal voltage of the heated oxygen
sensor 1 is displayed.
HO2S1 (B2) [V] ×
HO2S2 (B1) [V] ×

The signal voltage of the heated oxygen
sensor 2 is displayed.
HO2S2 (B2) [V] ×
HO2S1 MNTR (B1)
[RICH/LEAN] ××

Display of heated oxygen sensor 1 signal
during air-fuel ratio feedback control:
RICH: means the mixture became “rich”,
and control is being affected toward a
leaner mixture.
LEAN: means the mixture became “lean”,
and control is being affected toward a rich
mixture.
After turning ON the ignition switch,
“RICH” is displayed until air-fuel mixture
ratio feedback control begins.

When the air-fuel ratio feedback is
clamped, the value just before the clamp-
ing is displayed continuously.
HO2S1 MNTR (B2)
[RICH/LEAN] ×
HO2S2 MNTR (B1)
[RICH/LEAN] ×

Display of heated oxygen sensor 2 signal:
RICH: means the amount of oxygen after
three way catalyst is relatively small.
LEAN: means the amount of oxygen after
three way catalyst is relatively large.

When the engine is stopped, a certain
value is indicated.
HO2S2 MNTR (B2)
[RICH/LEAN] ×
VHCL SPEED SE
[km/h] or [mph] ××

The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.

EC-844
[VK45DE]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2005 July 2005 FX
TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionABS00E4K
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:

B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)

A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)

MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionABS00E4L

Vehicle driven distance: More than 5,000 km (3,017 miles)

Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30 °C (68 - 86 °F)

Engine coolant temperature: 75 - 95 °C (167 - 203 °F)

Transmission: Warmed-up*1

Electrical load: Not applied*2

Engine speed: Idle
*1: After the engine is warmed up to normal operating temperature, drive vehicle until “ATF TEMP 1” (A/T fluid
temperature sensor signal) indicates more than 60 °C (140 °F).
*2: Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureABS00E4M
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-769, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2” and “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-845, "
Diagnostic Procedure" .
SEF601Z

DTC P0011, P0021 IVT CONTROL EC-865
[VK45DE]
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Revision: 2005 July 2005 FX
DTC P0011, P0021 IVT CONTROLPFP:23796
DescriptionABS007IO
SYSTEM DESCRIPTION
*: This signal is sent to the ECM through CAN communication line
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
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 intake valve timing (IVT) control sole-
noid valve depending on driving status. This makes it possible to control the shut/open timing of the intake
valve to increase engine torque in low/mid speed range and output in high-speed range.
COMPONENT INSPECTION
Intake Valve Timing Control Solenoid Valve
Intake Valve Timing (IVT) control solenoid valve is activated by ON/
OFF pulse duty (ratio) signals from the ECM.
The IVT control solenoid valve changes the oil amount and direction
of flow through intake valve timing control unit or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
Sensor Input signal to ECM function ECM Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed
Intake valve
timing control Intake valve timing control
solenoid valve
Intake valve timing control position sensor Intake valve timing signal
Engine coolant temperature sensor Engine coolant temperature
Wheel sensor* Vehicle speed
PBIB1102E
PBIB1842E

DTC P0031, P0032, P0051, P0052 HO2S1 HEATER EC-877
[VK45DE]
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Revision: 2005 July 2005 FX
DTC P0031, P0032, P0051, P0052 HO2S1 HEATERPFP:22690
DescriptionABS007IW
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 1 heater corresponding to the engine speed
and engine coolant temperature. The duty percent varies with engine coolant temperature when engine is
started.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeABS007IX
Specification data are reference values.
On Board Diagnosis LogicABS007IY
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Heated oxygen sensor 1
heater control Heated oxygen sensor 1 heater
Engine coolant temperature sensor Engine coolant temperature
Engine speed rpm Heated oxygen sensor 1 heater
Above 3,000 OFF
Below 3,000 after warming up ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)
HO2S1 HTR (B2)

Engine: After warming up

Engine speed: Below 3,000 rpm ON

Engine speed: Above 3,000 rpm OFF
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0031
0031
(Bank 1) Heated oxygen
sensor 1 heater
control circuit low The current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively low voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)

Harness or connectors
(The heated oxygen sensor 1 heater circuit is
open or shorted.)

Heater oxygen sensor 1 heater
P0051
0051
(Bank 2)
P0032
0032
(Bank 1) Heated oxygen
sensor 1 heater
control circuit high The current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively high voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)

Harness or connectors
(The heated oxygen sensor 1 heater circuit is
shorted.)

Heater oxygen sensor 1 heater
P0052
0052
(Bank 2)

DTC P0037, P0038, P0057, P0058 HO2S2 HEATER EC-885
[VK45DE]
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Revision: 2005 July 2005 FX
DTC P0037, P0038, P0057, P0058 HO2S2 HEATERPFP:226A0
DescriptionABS007J4
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeABS007J5
Specification data are reference values.
On Board Diagnosis LogicABS007J6
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Heated oxygen sensor 2
heater control Heated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600 OFF
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 ON
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 load ON

Engine speed: Above 3,600 rpm OFF
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0037
0037
(Bank 1) Heated oxygen
sensor 2 heater
control circuit low The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit is
open or shorted.)

Heater oxygen sensor 2 heater
P0057
0057
(Bank 2)
P0038
0038
(Bank 1) Heated oxygen
sensor 2 heater
control circuit high The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to
ECM through the heated oxygen sensor 2
heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit is
shorted.)

Heater oxygen sensor 2 heater
P0058
0058
(Bank 2)

EC-914
[VK45DE]
DTC P0117, P0118 ECT SENSOR
Revision: 2005 July 2005 FX
DTC P0117, P0118 ECT SENSORPFP:22630
Component DescriptionABS007K0
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.

*: These data are reference values and are measured between ECM terminal 73
(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 LogicABS007K1
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 k
Ω
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.1 - 2.9
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
P0117
0117 Engine coolant tem-
perature sensor cir-
cuit low input An 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
0118 Engine coolant tem-
perature sensor cir-
cuit high input An excessively high voltage from the sensor is
sent to ECM.
Detected items Engine operating condition in fail-safe mode
Engine coolant temper- ature sensor circuit Engine coolant temperature will be determined by ECM based on the time after turning ignition switch ON
or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned ON or START 40 °C (104 °F)
More than approx. 4 minutes after ignition ON or START 80 °C (176 °F)
Except as shown above 40 - 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-917
[VK45DE]
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Revision: 2005 July 2005 FX
Diagnostic ProcedureABS007K4
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-861, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK ECT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine coolant temperature (ECT) sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between ECT sensor terminal 1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING RART
Check the following.

Harness connector F261, F24

Harness for open or short between ECM and engine coolant temperature sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB2195E
Voltage: Approximately 5V
PBIB1515E
PBIB0080E