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Home >> Nissan-Datsun >> 2021 >> Frontier PRO-4X >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (1 Of 3) >> 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.
  • For reference values of the following items, refer to Reference Value .

Monitored Item 

Monitored item

Unit

Monitor Item Selection

Description

Remarks

ECU INPUT SIGNALS

MAIN SIGNALS

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.

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

The power supply voltage of ECM is displayed.

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.

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.

FUEL T/TMP SE

deg. C or deg. F

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

FUEL LEVEL SE

V

x

The signal voltage of the fuel level sensor is displayed.

EVAP SYS PRES

V

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

CAL/LD VALUE

%

"Calculated load value" indicates the value of the current air flow divided by peak air flow.

HO2S2 (B1)

V

x

x

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

HO2S2 (B2)

ENG OIL TEMP

deg. C or deg. F

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

A/F ALPHA-B1

%

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.
  • Specification value is indicated on monitor screen under the following conditions.
    • Reference: Select
    • Display type: Line graph

A/F ALPHA-B2

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)

ATOM PRES SEN 2

V

x

The signal voltage from the manifold absolute pressure (MAP) sensor is displayed.

EXH/V TIM B1

deg. CA

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

EXH/V TIM B2

Ignition timing

deg

x

Indicates the ignition timing computed by ECM according to the input signals.

NOTE: Indicates degree from BTDC (Before Top Dead Center) of compression stroke.
  • When the engine is stopped, a certain value is indicated.

FAN DUTY

%

Indicates a command value for cooling fan. The value is calculated by ECM based on input signals.

FUEL PUMP DUTY

--

The control condition of the fuel pump control module (FPCM) (determined by ECM according to the input signals) is indicated.

BAT TEMP SEN

V

The signal voltage from the battery temperature sensor is displayed.

THRTL STK CNT B1

--

NOTE: The item is indicated, but not used.

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.

TRVL AFTER MIL

km or mile

Distance traveled while MIL is activated.

B/FUEL SCHDL

ms

x

"Base fuel schedule" indicates the fuel injection pulse width programmed into ECM, prior to any learned on board correction.

Specification value is indicated on monitor screen under the following conditions.

  • Reference: Select
  • Display type: Line graph

MASS AIRFLOW

g/s

Indicates the mass air flow computed by ECM according to the signal voltage of the mass air flow sensor.

FUEL PRES SEN

MPa

Indicates the fuel rail pressure computed by ECM according to the input signals.

ACCEL SEN 1

V

The accelerator pedal position sensor signal voltage is displayed.

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

ACCEL SEN 2

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, they differs from ECM terminal voltage signal.

TP SEN 2-B1

I/P PULLY SPD

RPM

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

VEHICLE SPEED

km/h or mph

The vehicle speed computed from the vehicle speed signal sent from TCM is displayed.

TUMBLE POS SEN

V

The intake manifold runner control valve position sensor signal voltage is displayed.

AC PRESS SEN

V

The signal voltage from the refrigerant pressure sensor 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.

A/F SEN1 (B2)

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

The preset vehicle speed is displayed.

VTC DTY EX B1

%

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

VTC DTY EX B2

BAT CUR SEN

The signal voltage of battery current sensor is displayed.

A/F ADJ-B1

--

Indicates the correction of 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

INT/V TIM (B1)

deg. CA

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

INT/V TIM (B2)

H/P FUEL PUMP DEG

deg

Displays ECM-calculated fuel discharge position of the high pressure fuel pump.

FUEL PRES SEN V

V

The signal voltage of FRP sensor is displayed.

EOP SENSOR

V

The signal voltage of EOP sensor is displayed.

ECM TEMP 1

deg. C

The ECM temperature is indicated.

ECM TEMP 2

Mass air flow sensor (Hz) B1

Hz

The signal frequency of the mass air flow sensor bank 1 is displayed.

  • Specification value is indicated on monitor screen under the following conditions.
    • Reference: Select
    • Display type: Line graph

EXHAUST GAS TEMP SEN 1 B1

V

The signal voltage of exhaust gas temperature sensor is displayed.

Exhaust gas temp sensor 1 B2

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.

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 signal) is indicated.

P/N POSI SW

On/Off

x

x

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

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 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.

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)

x

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.

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.

BRAKE SW

On/Off

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

COMBUSTION

Mode1

These items are displayed but are not applicable to this model.

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 condition determined by ECM according to the input signals.

FPCM

Hi/Mid/Low/Off

The control condition of the fuel pump control module (FPCM) (determined by ECM according to the input signals) is indicated.

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.

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)

BRAKE SW2

On/Off

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

BRAKE SW1

On/Off

Indicates [On/Off] condition from brake pedal position switch signal.

SET SW

On/Off

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

RESUME/ACC SW

On/Off

Indicates [On/Off] condition from ACCEL/RES switch signal.

CANCEL SW

On/Off

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

MAIN SW

On/Off

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

SET LAMP

On/Off

Indicates [On/Off] condition of SET lamp determined by the ECM according to the input signals.

AT OD CANCEL

On/Off

Indicates [On/Off] condition of AT O/D cancel request signal.

AT OD MONITOR

On/Off

Indicates [On/Off] condition of AT O/D according to the input signal from the TCM.

CRUISE LAMP

On/Off

Indicates [On/Off] condition of CRUISE lamp determined by the ECM according to the input signals.

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.

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.

ALT DUTY SIG

On/Off

The control condition of the power generation voltage variable control (determined by ECM according to the input signals) is indicated.

  • On: Power generation voltage variable control is active.
  • Off: Power generation voltage variable control is inactive.

HO2 S2 DIAG1 (B2)

INCMP/CMPLT

Indicates DTC P0159 self-diagnosis (delayed response) condition.

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

HO2 S2 DIAG1 (B1)

INCMP/CMPLT

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

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

HO2 S2 DIAG2 (B2)

INCMP/CMPLT

Indicates DTC P0159 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.

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.

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.

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.

SYSTEM 1 DIAGNOSIS B B2

ABSENT/PRSENT

Indicates DTC P219B self-diagnosis condition.

  • ABSNT: Self-diagnosis standby
  • PRSNT: Under self-diagnosis

SYSTEM 1 DIAGNOSIS B B1

ABSENT/PRSENT

Indicates DTC P219A self-diagnosis condition.

  • ABSNT: Self-diagnosis standby
  • PRSNT: Under self-diagnosis

A/F SEN1 DIAG3 (B2)

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.

A/F SEN1 DIAG3 (B1)

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.

DI timing SOI multi inj step1

BTDC

These items are displayed but not used.

Di inj pulse B1

ms

ECM-calculated injection pulse width of the direct fuel injector on the bank 1 side.

Di inj pulse B2

ms

These items are displayed but not used.

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