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Home >> Nissan-Datsun >> 2021 >> Maxima Platinum >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (1 Of 2) >> System Description >> Diagnosis System (ECM) >> CONSULT Function >> Data Monitor Mode
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Data Monitor Mode

NOTE: The following table includes information (items) inapplicable to this vehicle. For information (items) applicable to this vehicle, refer to CONSULT display items.

Monitored Item 

For reference values of the following items, refer to Reference Value .

x: Applicable

Monitored item

Unit

Monitor Item Selection

Description

Remarks

ECU INPUT SIGNALS

MAIN SIGNALS

ENG SPEED

RPM

x

x

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.

B/FUEL SCHDL

ms

x

x

"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

%

x

The mean value of the air-fuel ratio feedback correction 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

%

x

COOLANT TEMP/S

deg. C or deg. F

x

x

The engine coolant temperature (determined 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.

A/F SEN1 (B1)

V

x

x

The A/F signal computed from the input signal of the air fuel ratio (A/F) sensor 1 is displayed.

HO2S2 (B1)

V

x

x

The signal voltage of the heated oxygen sensor 2 is displayed.

HO2S2 (B2)

V

x

x

HO2S2 MNTR(B1)

RICH/LEAN

x

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

x

VHCL SPEED SE

km/h or mph

x

x

The vehicle speed computed from the vehicle speed signal sent from combination meter is displayed.

BATTERY VOLT

V

x

x

The power supply voltage of ECM is displayed.

ACCEL SEN 1

V

x

x

The accelerator pedal position sensor signal voltage is displayed.

ACCEL SEN 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.

ACCEL SEN 2

V

x

TP SEN 1-B1

V

x

x

The throttle position sensor signal voltage is displayed.

TP SEN 2-B1 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.

TP SEN 2-B1

V

x

x

FUEL T/TMP SE

deg. C or deg. F

x

The fuel temperature (determined by the signal voltage of the fuel tank temperature sensor) is displayed.

EVAP SYS PRES

V

x

The signal voltage of EVAP control system pressure sensor is displayed.

FUEL LEVEL SE

V

x

The signal voltage of the fuel level sensor is displayed.

START SIGNAL

On/Off

x

x

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 displayed regardless of the starter signal.

CLSD THL POS

On/Off

x

x

Indicates idle position [On/Off] computed by ECM according to the accelerator pedal position sensor signal.

AIR COND SIG

On/Off

x

x

Indicates [On/Off] condition of the air conditioner switch as determined by the air conditioner signal.

PW/ST SIGNAL

On/Off

x

x

[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

x

x

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 lighting switch are OFF.

IGNITION SW

On/Off

x

x

Indicates [On/Off] condition from ignition switch signal.

HEATER FAN SW

On/Off

x

Indicates [On/Off] condition from the heater fan switch signal.

BRAKE SW

On/Off

x

Indicates [On/Off] condition from the stop lamp switch signal.

INJ PULSE-B1

msec

x

Indicates the actual fuel injection pulse width compensated by ECM according to the input signals.

When the engine is stopped, a certain computed value is indicated.

INJ PULSE-B2

msec

IGN TIMING

BTDC

x

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

PURG VOL C/V

%

  • Indicates the EVAP canister purge volume control solenoid valve control value computed by the ECM according to the input signals.
  • The opening becomes larger as the value increases.

INT/V TIM (B1)

deg. CA

x

Indicates [ deg. CA] of intake camshaft advance angle.

INT/V TIM (B2)

deg. CA

x

x

INT/V SOL (B1)

%

x

  • The control value 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)

%

x

VIAS S/V-1

On/Off

x

The control condition of the VIAS control solenoid valve 1 (determined by ECM according to the input signals) is indicated.

  • On: VIAS control solenoid valve 1 is operating.
  • Off: VIAS control solenoid valve 1 is not operating.

AIR COND RLY

On/Off

x

The air conditioner relay control condition (determined by ECM according to the input signals) is indicated.

ENGINE MOUNT

IDLE/TRVL

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
  • TRVL: Engine speed is above 950 RPM

FUEL PUMP RLY

On/Off

x

Indicates the fuel pump relay control condition 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

x

Indicates the throttle control motor relay control condition determined by the ECM according to the input signals.

A/F S1 HTR(B2)

%

x

  • 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.

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

x

Indicates the engine speed computed from the input speed sensor signal.

VEHICLE SPEED

km/h or mph

x

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 performed yet.
  • CMPLT: Idle Air Volume Learning has already been performed successfully.

TRVL AFTER MIL

km or mile

Distance traveled while MIL is activated.

ENG OIL TEMP

deg. C or deg. F

x

The engine oil temperature (determined by the signal voltage of the engine oil temperature sensor) is displayed.

A/F S1 HTR(B1)

%

x

  • 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.

VHCL SPEED SE

km/h or mph

The vehicle speed computed from the vehicle speed signal sent from combination meter is displayed.

SET VHCL SPD

km/h or mph

x

  • The preset vehicle speed is displayed.

MAIN SW

On/Off

x

Indicates [On/Off] condition from MAIN switch signal.

CANCEL SW

On/Off

x

Indicates [On/Off] condition from CANCEL switch signal.

RESUME/ACC SW

On/Off

x

Indicates [On/Off] condition from RESUME/ACCELERATE switch signal.

SET SW

On/Off

x

Indicates [On/Off] condition from SET/COAST switch signal.

BRAKE SW1

On/Off

x

Indicates [On/Off] condition from Brake pedal position switch signal or ASCD clutch switch.

BRAKE SW2

On/Off

x

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 according 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 determined by the ECM according to the input signals.

VIAS S/V-2

On/Off

The control condition of the VIAS control solenoid valve 2 (determined by ECM according to the input signals) is indicated.

  • On: VIAS control solenoid valve 2 is operating.
  • Off: VIAS control solenoid valve 2 is not operating.

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

A/F ADJ-B1

--

Indicates the correction of a factor stored in ECM. The factor is calculated from the difference between the target air-fuel ratio stored in ECM and the air-fuel ratio calculated from A/F sensor 1 signal.

A/F ADJ-B2

--

P/N POSI SW

On/Off

x

x

Indicates [On/Off] condition from the park/neutral position (PNP) signal.

INT/A TEMP SE

deg. C or deg. F

x

x

The intake air temperature (determined by the signal voltage of the intake air temperature sensor) is indicated.

AC PRESS SEN

V

x

The signal voltage from the refrigerant pressure sensor is displayed.

A/F SEN1 (B2)

V

x

x

The A/F signal computed from the input signal of the air fuel ratio (A/F) sensor 1 is displayed.

EVAP LEAK DIAG

Yet/CMPLT

Indicates the condition of EVAP leak diagnosis.

  • YET: EVAP leak diagnosis has not been performed yet.
  • CMPLT: EVAP leak diagnosis has been performed successfully.

EVAP DIAG READY

On/Off

Indicates the ready condition of EVAP leak diagnosis.

  • On: Diagnosis has been ready condition.
  • Off: Diagnosis has not been ready condition.

BAT TEMP SEN

V

x

The signal voltage from the battery temperature sensor is displayed.

THRTL STK CNT B1*

--

--

HO2 S2 DIAG1(B2)

INCMP/CMPLT

Indicates DTC P0139 self-diagnosis (delayed response) condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

A/F SEN1 DIAG1(B2)

INCMP/CMPLT

Indicates DTC P015C or P015D self-diagnosis condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

A/F SEN1 DIAG1(B1)

INCMP/CMPLT

Indicates DTC P015A or P015B self-diagnosis condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

A/F SEN1 DIAG2(B2)

INCMP/CMPLT

Indicates DTC P014E or P014F self-diagnosis condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

A/F SEN1 DIAG2(B1)

INCMP/CMPLT

Indicates DTC P014C or P014D self-diagnosis condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

A/F SEN1 DIAG3(B2)

ABSNT/PRSNT

Indicates DTC P014E, P014F, P015C or P015D self-diagnosis condition.

  • ABSNT: The vehicle condition is not within the diagnosis range.
  • PRSNT: The vehicle condition is within the diagnosis range.

A/F SEN1 DIAG3(B1)

ABSNT/PRSNT

Indicates DTC P014C, P014D, P015A or P015B self-diagnosis condition.

  • ABSNT: The vehicle condition is not within the diagnosis range.
  • PRSNT: The vehicle condition is within the diagnosis range.

HO2 S2 DIAG2(B2)

INCMP/CMPLT

Indicates DTC P0139 self-diagnosis (slow response) condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

HO2 S2 DIAG2(B1)

INCMP/CMPLT

Indicates DTC P0139 self-diagnosis (slow response) condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

EOP SENSOR

mV

x

The signal voltage of EOP sensor is displayed.

HO2 S2 DIAG1(B1)

INCMP/CMPLT

Indicates DTC P0139 self-diagnosis (delayed response) condition.

  • INCMP: Self-diagnosis is incomplete.
  • CMPLT: Self-diagnosis is complete.

MASS AIR FLOW SENSOR (Hz)

Hz

x

The signal frequency of the mass air flow sensor is displayed.

EXH/V TIM B1

deg. CA

x

x

Indicates [ deg. CA] of exhaust camshaft advance angle.

EXH/V TIM B2

deg. CA

x

x

VTC DTY EX B1

%

--

VTC DTY EX B2

%

--

A/F-S ATMSPHRC CRCT B1

--

Displays a determined value of atmospheric correction factor necessary for correcting an A/F sensor signal input to ECM. The signal used for the correction is an A/F sensor signal transmitted while driving under atmospheric pressure.

A/F-S ATMSPHRC CRCT B2

--

Displays a determined value of atmospheric correction factor necessary for correcting an A/F sensor signal input to ECM. The signal used for the correction is an A/F sensor signal transmitted while driving under atmospheric pressure.

A/F-S ATMSPHRC CRCT UP B1

count

Displays the number of updates of the A/F sensor atmospheric correction factor.

A/F-S ATMSPHRC CRCT UP B2

count

Displays the number of updates of the A/F sensor atmospheric correction factor.

SYSTEM 1 DIAGNOSIS A B2

INCMP/CMPLT

  • Indicates DTC P219B self-diagnosis condition.
    • INCMP: Self-diagnosis is incomplete.
    • CMPLT: Self-diagnosis is complete.

SYSTEM 1 DIAGNOSIS A B1

INCMP/CMPLT

  • Indicates DTC P219A self-diagnosis condition.
    • INCMP: Self-diagnosis is incomplete.
    • CMPLT: Self-diagnosis is complete.

SYSTEM 1 DIAGNOSIS B B2

ABSNT/PRSNT

  • Indicates DTC P219B self-diagnosis condition.
    • ABSNT: Self-diagnosis standby
    • PRSNT: Under self-diagnosis

SYSTEM 1 DIAGNOSIS B B1

ABSNT/PRSNT

  • Indicates DTC P219A self-diagnosis condition.
    • ABSNT: Self-diagnosis standby
    • PRSNT: Under self-diagnosis

*: The item is indicated, but not used

NOTE: Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.