Nissan Maxima. Manual - part 414

EC-140

< SYSTEM DESCRIPTION >

[VQ35DE]

DIAGNOSIS SYSTEM (ECM)

B/FUEL SCHDL

ms

• “Base fuel schedule” indicates the fuel injection 

pulse width programmed into ECM, prior to any 
learned on board correction.

• When engine is running, specification 

range is indicated in “SPEC”.

A/F ALPHA-B1

%

• The mean value of the air-fuel ratio feedback cor-

rection factor per cycle is indicated.

• When the engine is stopped, a certain 

value is indicated.

• This data also includes the data for 

the air-fuel ratio learning control.

• When engine is running, specification 

range is indicated in “SPEC”.

A/F ALPHA-B2

COOLANT TEMP/S

°C or °F

• The engine coolant temperature (determined by 

the signal voltage of the engine coolant tempera-
ture sensor) is displayed.

• When the engine coolant temperature 

sensor is open or short-circuited, 
ECM enters fail-safe mode. The en-
gine coolant temperature determined 
by the ECM is displayed.

A/F SEN1 (B1)

V

• The A/F signal computed from the input signal of 

the air fuel ratio (A/F) sensor 1 is displayed.

A/F SEN1 (B2)

HO2S2 (B1)

V

• The signal voltage of the heated oxygen sensor 2 

is displayed.

HO2S2 (B2)

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)

VHCL SPEED SE

km/h or mph

• The vehicle speed computed from the vehicle 

speed signal sent from combination meter is dis-
played.

BATTERY VOLT

V

• The power supply voltage of ECM is displayed.

ACCEL SEN 1

V

• The accelerator pedal position sensor signal volt-

age is displayed.

• ACCEL SEN 2 signal is converted by 

ECM internally. Thus, it differs from 
ECM terminal voltage signal.

ACCEL SEN 2

TP SEN 1-B1

V

• The throttle position sensor signal voltage is dis-

played.

• TP SEN 2-B1 signal is converted by 

ECM internally. Thus, it differs from 
ECM terminal voltage signal.

TP SEN 2-B1

FUEL T/TMP SE

°C or °F

• The fuel temperature (determined by the signal 

voltage of the fuel tank temperature sensor) is 
displayed.

INT/A TEMP SE

°C or °F

• The intake air temperature (determined by the 

signal voltage of the intake air temperature sen-
sor) is indicated.

EVAP SYS PRES

V

• The signal voltage of EVAP control system pres-

sure sensor is displayed.

FUEL LEVEL SE

V

• The signal voltage of the fuel level sensor is dis-

played.

START SIGNAL

ON/OFF

• Indicates start signal status [ON/OFF] computed 

by the ECM according to the signals of engine 
speed and battery voltage.

• After starting the engine, [OFF] is dis-

played regardless of the starter sig-
nal.

CLSD THL POS

ON/OFF

• Indicates idle position [ON/OFF] computed by 

ECM according to the accelerator pedal position 
sensor signal.

AIR COND SIG

ON/OFF

• Indicates [ON/OFF] condition of the air condition-

er switch as determined by the air conditioner sig-
nal.

P/N POSI SW

ON/OFF

• Indicates [ON/OFF] condition from the park/neu-

tral position (PNP) signal.

Monitored item

Unit

Description

Remarks

DIAGNOSIS SYSTEM (ECM)

EC-141

< SYSTEM DESCRIPTION >

[VQ35DE]

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PW/ST SIGNAL

ON/OFF

• [ON/OFF] condition of the power steering system 

(determined by the signal voltage of the power 
steering pressure sensor) is indicated.

LOAD SIGNAL

ON/OFF

• Indicates [ON/OFF] condition from the electrical 

load signal.
ON: Rear window defogger switch is ON and/or 
lighting switch is in 2nd position.
OFF: Both rear window defogger switch and light-
ing switch are OFF.

IGNITION SW

ON/OFF

• Indicates [ON/OFF] condition from ignition switch 

signal.

HEATER FAN SW

ON/OFF

• Indicates [ON/OFF] condition from the heater fan 

switch signal.

BRAKE SW

ON/OFF

• Indicates [ON/OFF] condition from the stop lamp 

switch signal.

INJ PULSE-B1

msec

• Indicates the actual fuel injection pulse width 

compensated by ECM according to the input sig-
nals.

• When the engine is stopped, a certain 

computed value is indicated.

INJ PULSE-B2

IGN TIMING

BTDC

• Indicates the ignition timing computed by ECM 

according to the input signals.

• When the engine is stopped, a certain 

value is indicated.

CAL/LD VALUE

%

• “Calculated load value” indicates the value of the 

current air flow divided by peak air flow.

MASS AIRFLOW

g/s

• Indicates the mass air flow computed by ECM ac-

cording to the signal voltage of the mass air flow 
sensor.

PURG VOL C/V

%

• Indicates the EVAP canister purge volume con-

trol solenoid valve control value computed by the 
ECM according to the input signals.

• The opening becomes larger as the value in-

creases.

INT/V TIM(B1)

°CA

• Indicates [

°CA] of intake camshaft advance an-

gle. 

INT/V TIM(B2)

EXH/V TIM B1

°CA

• Indicates [

°CA] of exhaust camshaft retard angle. 

EXH/V TIM B2

INT/V SOL(B1)

%

• The control value of the intake valve timing con-

trol solenoid valve (determined by ECM accord-
ing to the input signals) is indicated.

• The advance angle becomes larger as the value 

increases.

INT/V SOL(B2)

VTC DTY EX B1

%

• The control value of the exhaust valve timing con-

trol magnet retarder (determined by ECM accord-
ing to the input signals) is indicated.

• The retard angle becomes larger as the value in-

creases.

VTC DTY EX B2

VIAS S/V-1

ON/OFF

• The control condition of the VIAS control solenoid 

valve 1 (determined by ECM according to the in-
put signals) is indicated.
ON: VIAS control solenoid valve 1 is operating.
OFF: VIAS control solenoid valve 1 is not operat-
ing.

VIAS S/V-2

ON/OFF

• The control condition of the VIAS control solenoid 

valve 2 (determined by ECM according to the in-
put signals) is indicated.
ON: VIAS control solenoid valve 2 is operating.
OFF: VIAS control solenoid valve 2 is not operat-
ing.

Monitored item

Unit

Description

Remarks

EC-142

< SYSTEM DESCRIPTION >

[VQ35DE]

DIAGNOSIS SYSTEM (ECM)

AIR COND RLY

ON/OFF

• The air conditioner relay control condition (deter-

mined by ECM according to the input signals) is 
indicated.

ENGINE MOUNT

IDLE/RUN

• The control condition of the electronic controlled 

engine mount (determined by ECM according to 
the input signals) is indicated.
IDLE: Engine speed is below 950 rpm
RUN: Engine speed is above 950 rpm

FUEL PUMP RLY

ON/OFF

• Indicates the fuel pump relay control condition 

determined by ECM according to the input sig-
nals.

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 (deter-

mined by ECM according to the input signals) is 
indicated.
HI: High speed operation
MID: Middle speed operation
LOW: Low speed operation
OFF: Stop

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)

I/P PULLY SPD

rpm

• Indicates the engine speed computed from the in-

put speed sensor signal.

VEHICLE SPEED

km/h or mph

• The vehicle speed computed from the vehicle 

speed signal sent from TCM is displayed.

IDL A/V LEARN

YET/CMPLT

• Displays the condition of idle air volume learning

YET: Idle Air Volume Learning has not been per-
formed yet.
CMPLT: Idle Air Volume Learning has already 
been performed successfully.

ENG OIL TEMP

°C or °F

• The engine oil temperature (determined by the 

signal voltage of the engine oil temperature sen-
sor) is displayed.

TRVL AFTER MIL

km or mile

• Distance traveled while MIL is activated.

A/F S1 HTR(B1)

%

• Air fuel ratio (A/F) sensor 1 heater control value 

computed by ECM according to the input signals.

• The current flow to the heater becomes larger as 

the value increases.

A/F S1 HTR(B2)

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 vehicle 

speed signal sent from combination meter 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 MAIN switch 

signal.

CANCEL SW

ON/OFF

• Indicates [ON/OFF] condition from CANCEL 

switch signal.

Monitored item

Unit

Description

Remarks

DIAGNOSIS SYSTEM (ECM)

EC-143

< SYSTEM DESCRIPTION >

[VQ35DE]

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RESUME/ACC SW

ON/OFF

• Indicates [ON/OFF] condition from RESUME/AC-

CELERATE switch signal.

SET SW

ON/OFF

• Indicates [ON/OFF] condition from SET/COAST 

switch signal.

BRAKE SW1

ON/OFF

• Indicates [ON/OFF] condition from ASCD brake 

switch signal.

BRAKE SW2

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 decreased to excessively 
low 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 excessively 
low, and ASCD operation is cut off.

AT OD MONITOR

ON/OFF

• Indicates [ON/OFF] condition of CVT O/D ac-

cording to the input signal from the TCM.

AT OD CANCEL

ON/OFF

• Indicates [ON/OFF] condition of CVT O/D cancel 

request signal.

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 deter-

mined by the ECM according to the input signals.

EXH V/T LEARN

YET/CMPLT

• Displays the condition of exhaust valve timing 

control learning
YET: Exhaust valve timing control Learning has 
not been performed yet.
CMPLT: Exhaust valve timing control Learning 
has already been performed successfully.

ALT DUTY SIG

ON/OFF

• The control condition of the power generation 

voltage variable control (determined by ECM ac-
cording to the input signals) is indicated.
ON: Power generation voltage variable control is 
active.
OFF: Power generation voltage variable control 
is inactive.

A/F ADJ-B1

—

• Indicates the correction of a factor stored in ECM. 

The factor is calculated from the difference be-
tween the target air-fuel ratio stored in ECM and 
the air-fuel ratio calculated from A/F sensor 1 sig-
nal.

A/F ADJ-B2

BAT CUR SEN

mV

• The signal voltage of battery current sensor is 

displayed.

ALT DUTY

%

• Indicates the duty ratio of the power generation 

command value. The ratio is calculated by ECM 
based on the battery current sensor signal.

THRTL STK CNT B1

*

—

—

EVAP LEAK DIAG

YET/CMPLT

• Indicates the condition of EVAP leak diagnosis.
- YET: EVAP leak diagnosis has not been per-

formed yet.

- CMPLT: EVAP leak diagnosis has been per-

formed successfully.

Monitored item

Unit

Description

Remarks