2004 INFINITI FX35 oxygen

EC-114
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
DATA MONITOR MODE
Monitored Item
×: Applicable
Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed from
the signal of the crankshaft position sensor
(POS) and camshaft position sensor
(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 sen-
sor is displayed.
When the engine is stopped, a cer-
tain value is indicated.
B/FUEL SCHDL
[msec]×

Base fuel schedule indicates the fuel injec-
tion pulse width programmed into ECM,
prior to any learned on board correction.
A/F ALPHA-B1 [%]×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indicated.

When the engine is stopped, a cer-
tain 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 tempera-
ture sensor is open or short-circuited,
ECM enters fail-safe mode. The
engine coolant temperature deter-
mined 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 mix-
ture ratio feedback control begins.

When the air-fuel ratio feedback is
clamped, the value just before the
clamping 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 cer-
tain value is indicated.
HO2S2 MNTR (B2)
[RICH/LEAN]×
VHCL SPEED SE
[km/h] or [mph]××

The vehicle speed computed from the vehi-
cle speed signal sent from combination
meter is displayed.
BATTERY VOLT [V]××

The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V]××

The accelerator pedal position sensor sig-
nal voltage is displayed.
ACCEL SEN2 signal is converted by
ECM internally. Thus, they differs
from ECM terminal voltage signal. ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××

The throttle position sensor signal voltage
is displayed.
THRTL SEN2 signal is converted by
ECM internally. Thus, they differs
from ECM terminal voltage signal. THRTL SEN 2 [V]×

EC-116
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
PURG VOL C/V [%]

Indicates the EVAP canister purge volume
control solenoid valve control value com-
puted by the ECM according to the input
signals.

The opening becomes larger as the value
increases.
INT/V TIM (B1) [°CA]

Indicates [°CA] of intake camshaft
advanced angle.
INT/V TIM (B2) [°CA]
INT/V SOL (B1) [%]

The control condition of the intake valve
timing control solenoid valve (determined
by ECM according to the input signals) is
indicated.

The advance angle becomes larger as the
value increases. INT/V SOL (B2) [%]
AIR COND RLY
[ON/OFF]×

The air conditioner relay control condition
(determined by ECM according to the input
signals) is indicated.
FUEL PUMP RLY
[ON/OFF]×

Indicates the fuel pump relay control condi-
tion determined by ECM according to the
input signals.
VENT CONT/V
[ON/OFF]

The control condition of the EVAP canister
vent control valve (determined by ECM
according to the input signals) is indicated.
ON: Closed
OFF: Open
THRTL RELAY
[ON/OFF]

Indicates the throttle control motor relay
control condition determined by the ECM
according to the input signals.
COOLING FAN
[HI/MID/LOW/OFF]

The control condition of the cooling fan
(determined by ECM according to the input
signals) is indicated.
HI: High speed operation
MID: Middle speed operation
LOW: Low speed operation
OFF: Stop
HO2S1 HTR (B1)
[ON/OFF]

Indicates [ON/OFF] condition of heated
oxygen sensor 1 heater determined by
ECM according to the input signals. HO2S1 HTR (B2)
[ON/OFF]
HO2S2 HTR (B1)
[ON/OFF]

Indicates [ON/OFF] condition of heated
oxygen sensor 2 heater determined by
ECM according to the input signals. HO2S2 HTR (B2)
[ON/OFF]
I/P PULLY SPD
[rpm]

Indicates the engine speed computed from
the turbine revolution sensor signal.
VEHICLE SPEED
[km/h] or [MPH]

Indicates the vehicle speed computed from
the revolution sensor signal.
IDL A/V LEARN
[YET/CMPLT]

Display the condition of idle air volume
learning
YET: Idle air volume learning has not been
performed yet.
CMPLT: Idle air volume learning has
already been performed successfully. Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-117
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45TRVL AFTER MIL
[km] or [mile]
Distance traveled while MIL is activated.
O2SEN HTR DTY
[%]

Indicates the heated oxygen sensor 1
heater control value computed by the ECM
according to the input signals.
AC PRESS SEN [V]

The signal voltage from the refrigerant
pressure sensor is displayed.
VHCL SPEED SE
[km/h] or [mph]

The vehicle speed computed from the vehi-
cle speed signal sent from TCM is dis-
played.
SET VHCL SPD
[km/h] or [mph]

The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]

Indicates [ON/OFF] condition from ON/
OFF(MAIN) switch signal.
CANCEL SW
[ON/OFF]

Indicates [ON/OFF] condition from CAN-
CEL switch signal.
RESUME/ACC SW
[ON/OFF]

Indicates [ON/OFF] condition from ACCEL/
RESUME switch signal.
SET SW
[ON/OFF]

Indicates [ON/OFF] condition from COAST/
SET switch signal.
BRAKE SW1 SW
[ON/OFF]

Indicates [ON/OFF] condition from ASCD
brake switch signal.
BRAKE SW2 SW
[ON/OFF]

Indicates [ON/OFF] condition of stop lamp
switch signal.
VHCL SPD CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed increased to exces-
sively high compared with the ASCD set
speed, and ASCD operation is cut off.
LO SPEED CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed decreased to exces-
sively low compared with the ASCD set
speed, and ASCD operation is cut off.
AT OD MONITOR
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D
according to the input signal from the TCM.
AT OD CANCEL
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D
cancel signal sent from the TCM.
CRUISE LAMP
[ON/OFF]

Indicates [ON/OFF] condition of CRUISE
lamp determined by the ECM according to
the input signals.
SET LAMP
[ON/OFF]

Indicates [ON/OFF] condition of SET lamp
determined by the ECM according to the
input signals. Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

EC-118
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Voltage [V]

Voltage, frequency, duty cycle or pulse
width measured by the probe.

Only # is displayed if item is unable
to be measured.

Figures with #s are temporary ones.
They are the same figures as an
actual piece of data which was just
previously measured. Frequency [msec],
[Hz] or [%]
DUTY-HI
DUTY-LOW
PLS WIDTH-HI
PLS WIDTH-LOWMonitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow
sensor specification is displayed.
When engine is running specification
range 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.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%]×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for the
air-fuel ratio learning control.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Heated oxygen sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch: OFF

Shift lever: P or N

Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil

DTC P0031, P0032, P0051, P0052 HO2S1 HEATER
EC-149
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0031, P0032, P0051, P0052 HO2S1 HEATERPFP:22690
DescriptionABS006LJ
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 ModeABS006LK
Specification data are reference values.
On Board Diagnosis LogicABS006LL
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 1
heater controlHeated oxygen sensor 1 heater
Engine coolant temperature sensor Engine coolant temperature
Engine speed rpm Heated oxygen sensor 1 heater
Above 3,600 OFF
Below 3,600 after warming up ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)
HO2S1 HTR (B2)

Engine: After warming up

Engine speed: Below 3,600 rpmON

Engine speed: Above 3,600 rpm OFF
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0031
0031
(Bank 1)Heated oxygen
sensor 1 heater
control circuit lowThe 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 highThe 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)

EC-152
[VQ35DE]
DTC P0031, P0032, P0051, P0052 HO2S1 HEATER
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
24 LHeated oxygen sensor 1
heater (bank 1)[Engine is running]

Warm-up condition

Engine speed is below 3,600 rpmApproximately 8V
[Engine is running]

Engine speed is above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB0519E

EC-154
[VQ35DE]
DTC P0031, P0032, P0051, P0052 HO2S1 HEATER
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnostic ProcedureABS006LO
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to EC-141, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2LHeated oxygen sensor 1
heater (bank 2)[Engine is running]

Warm-up condition

Engine speed is below 3,600 rpmApproximately 8V
[Engine is running]

Engine speed is above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB0519E
PBIB2195E

DTC P0031, P0032, P0051, P0052 HO2S1 HEATER
EC-155
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Revision: 2004 November 2004 FX35/FX45
2. CHECK HO2S1 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check voltage between HO2S1 terminal 2 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E18, F48

Fuse block (J/B) connector E201

10A fuse

Harness for open or short between heated oxygen sensor 1 and fuse
>> Repair harness or connectors.
4. CHECK HO2S1 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.Voltage: Battery voltage
PBIB1559E
PBIB0969E
DTCTe r m i n a l s
Bank
ECM Sensor
P0031, P0032 24 3 1
P0051, P0052 2 3 2
Continuity should exist.