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Home >> Nissan-Datsun >> 2021 >> Sentra S >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (1 Of 2) >> System Description >> Diagnosis System (ECM) >> Consult Function >> Diagnosis Description >> 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 Physical Values .

Monitored Item 

Monitored item

Unit

Description

Remarks

COOLANT TEMP/S

deg. C

The engine coolant temperature (determined by the signal voltage of the engine outlet 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

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.

EGR TEMP SEN

INT/A TEMP SE

deg. C or deg. F

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

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.

PURG VOL C/V

%

  • Indicates the control value of the EVAP canister purge volume control solenoid valve 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.

CAL/LD VALUE

%

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

HO2S2 (B1)

V

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

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

MAP SENSOR

V

The atmospheric pressure sensor signal voltage is displayed.

--

FUEL INJ TIM

BTDC

Indicates the fuel injection timing computed by ECM according to the input signals.

--

EXH/V TIM B1

deg. CA

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

--

EGR VALVE POSITION

deg

Indicates the EGR volume control valve angle

--

FAN DUTY

%

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

--

THRTL STK CNT B1

--

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

--

A/GRLL SHTTR POSITION

F/CLOSE

MOVING

F/OPEN

UNIDTF

Indicates the status of active grille shutter.

  • F/CLOSE: Active grille shutter is fully closed.
  • MOVING: Active grille shutter is in motion.
  • F/OPEN: Active grille shutter is fully opened.
  • UNIDTF: Unable to specify the shutter position.

--

ENG SPEED

RPM

Indicates the engine speed computed from the signal of the crankshaft position sensor and camshaft position sensor.

Accuracy becomes poor if engine speed drops below the idle RPM.

TRVL AFTER MIL

km or mile

Distance traveled while MIL is activated.

--

B/FUEL SCHDL

ms

"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 mass air flow sensor signal.

--

FUEL PRES SEN

MPa

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

--

ACCEL SEN 1

V

The signal voltage of the accelerator pedal position sensor 1 is displayed.

--

ACCEL SEN 2

V

The converted value of 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.

TP SEN 1-B1

V

The signal voltage of the throttle position sensor 1 B1 is displayed.

--

TP SEN 2-B1

V

The value converted from the signal voltage of the throttle position sensor 2 B1 is displayed.

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

I/P PULLY SPD

RPM

Indicates the engine speed computed from the input shaft revolution 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

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

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

The preset vehicle speed is displayed.

VTC DTY EX B1

%

  • The control value of the exhaust valve timing control solenoid valve (determined by ECM according to the input signals) is indicated.
  • The advance angle becomes larger as the value increases.

BAT CUR SEN

V

The signal voltage from the battery temperature sensor is displayed.

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.

INT/V TIM (B1)

deg. CA

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

H/P FUEL PUMP DEG

deg

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

FUEL PRES SEN V

mV

The signal voltage of FRP sensor is displayed.

EOP SENSOR

mV

The signal voltage of EOP sensor is displayed.

ECM TEMP 1

deg. C

Displays a temperature calculated from a signal of ECM temperature sensor 1.

ECM TEMP 2

deg. C

Displays a temperature calculated from a signal of ECM temperature sensor 2.

Mass air flow sensor (HZ) B1

Hz

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

EGR VALVE POSITION SEN

V

The signal voltage of EGR volume control valve position sensor is displayed.

LOAD SIGNAL

On/Off

Indicates [On/Off] condition of the electrical load signal.

  • ON...Rear window defogger switch is ON or lighting switch is in 2nd position.
  • OFF...Both rear window defogger switch and lighting switch are OFF.

--

AIR COND SIG

On/Off

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

--

PW/ST SIGNAL

On/Off

Indicates [On/Off] condition of the power steering system (determined by the signal voltage of the power steering pressure sensor signal).

--

P/N POSI SW

On/Off

Indicates [On/Off] condition from the reverse/neutral position 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

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

--

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.

IGNITION SW

On/Off

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

--

HEATER FAN SW

On/Off

Indicates [On/Off] condition from the heater blower ON 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.
  • DONE...Idle air volume learning has already been performed successfully.

--

BRAKE SW

On/Off

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

--

COMBUSTION

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

--

SWRL CONT S/V *

On/Off

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

  • ON: Closed
  • OFF: Open

--

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.

--

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.

--

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 SET - switch signal.

--

RESUME/ACC SW

On/Off

Indicates [On/Off] condition from 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 indicator determined by the ECM according to the input signals.

--

CRUISE LAMP

On/Off

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

A/GRLL SHTTR CALIBRATION

INCMP/ CMPLT

Indicates initial position learning status of active grille shutter.

  • CMPLT: The leaning is complete.
  • INCOMP: The learning is incomplete.

A/GRLL SHTTR CIRCUIT DIAG

OK/NG

Indicates the diagnosis result of active grille shutter circuit.

  • OK: Normal.
  • NG: Malfunction detected.

A/GRLL SHTTR TEMP DIAG

OK/NG

Indicates the diagnosis result of active grille shutter actuator temperature status.

  • OK: Normal.
  • NG: Abnormal temperature detected.

A/GRLL SHTTR OVER RUN

OK/NG

Indicates active grille shutter moves beyond normal moving limit.

  • OK: Normal.
  • NG: Malfunction detected.

A/GRLL SHTTR STUCK

OK/NG

Indicates the diagnosis result of active grille shutter stuck or the operation range less than normal.

  • OK: Normal.
  • NG: Malfunction detected.

A/GRLL SHTTR CALIB DIAG

OK/NG

Indicates the diagnosis result of initial position learning of active grille shutter.

  • OK: Normal.
  • NG: Deficiency detected.

HO2 S2 DIAG2 (B1)

INCMP/CMPLT

Indicates DTC P0139 self-diagnosis (slow response) 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.

FUEL LEVEL SE

V

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

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

--

ENG OIL TEMP

deg. C 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

MAP SENSOR

V

The atmospheric pressure sensor signal voltage is displayed.

A/F S1 HTR (B1)

%

  • Indicates the duty ratio of the Air fuel ratio (A/ F) sensor 1 heater computed by ECM according to the input signals.
  • The current flow to the heater becomes larger as the value increases.

EXH/V TIM B1

deg.CA

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

EGR VALVE POSITION

deg

Indicates the EGR volume control valve angle

FAN DUTY

%

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

THRTL STK CNT B1

--

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

A/GRLL SHTTR POSITION

F/CLOSE

MOVING

F/OPEN

UNIDTF

Indicates the status of active grille shutter.

  • F/CLOSE: Active grille shutter is fully closed.
  • MOVING: Active grille shutter is in motion.
  • F/OPEN: Active grille shutter is fully opened.
  • UNIDTF: Unable to specify the shutter position.

ENG SPEED

RPM

Indicates the engine speed computed from the signal of the crankshaft position sensor and camshaft position sensor.

Accuracy becomes poor if engine speed drops below the idle RPM.

TRVL AFTER MIL

km or mile

Distance traveled while MIL is activated.

B/FUEL SCHDL

ms

"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 mass air flow sensor signal.

--

FUEL PRES SEN

Mpa

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

--

ACCEL SEN 1

V

The signal voltage of the accelerator pedal position sensor 1 is displayed.

--

ACCEL SEN 2

V

The converted value of 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.

TP SEN 1-B1

V

The signal voltage of the throttle position sensor 1 B1 is displayed.

--

TP SEN 2-B1

V

The value converted from the signal voltage of the throttle position sensor 2 B1 is displayed.

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

I/P PULLY SPD

RPM

Indicates the engine speed computed from the input shaft revolution 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

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

--

VHCL SPEED SE

km/h or mph

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

--

VTC DTY EX B1

%

  • The control value of the exhaust valve timing control solenoid valve (determined by ECM according to the input signals) is indicated.
  • The advance angle becomes larger as the value increases.

--

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.

--

H/P FUEL PUMP DEG

deg

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

--

FUEL PRES SEN V

mV

The signal voltage of FRP sensor is displayed.

--

EOP SENSOR

mV

The signal voltage of EOP sensor is displayed.

--

ECM TEMP 1

deg. C

Displays a temperature calculated from a signal of ECM temperature sensor 1.

--

ECM TEMP 2

deg. C

Displays a temperature calculated from a signal of ECM temperature sensor 2.

--

Mass air flow sensor (HZ) B1

Hz

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

--

EGR VALVE POSITION SEN

V

The signal voltage of EGR volume control valve position sensor is displayed.

--

TOTAL DISTNC-OCS RST 1

Km

Total travel distance of odd meter when Oil Control System is reset.

--

TOTAL DISTNC-OCS RST 2

Km

Total travel distance of odd meter when Oil Control System is reset. (two times ago)

--

TOTAL DISTNC-OCS RST 3

Km

Total travel distance of odd meter when Oil Control System is reset. (three times ago)

--

DETERIORTN VL -OCS RST 1

--

Indicates deterioration condition of the engine oil when Oil Control System is reset.

--

DETERIORTN VL -OCS RST 2

--

Indicates deterioration condition of the engine oil when Oil Control System is reset. (two times ago)

--

DETERIORTN VL -OCS RST 3

--

Indicates deterioration condition of the engine oil when Oil Control System is reset. (two times ago)

--

TOTAL DISTNC-OCS WRN 1

Km

Total travel distance of odd meter when Oil Control System remaining distance is zero.

--

TOTAL DISTNC-OCS WRN 2

Km

Total travel distance of odd meter when Oil Control System remaining distance is zero. (two times ago)

--

TOTAL DISTNC-OCS WRN 3

Km

Total travel distance of odd meter when Oil Control System remaining distance is zero. (two times ago)

--

DETERIORTN VL-OCS WRN 1

--

Indicates deterioration condition of the engine oil when Oil Control System remaining distance is zero.

--

DETERIORTN VL-OCS WRN 2

--

Indicates deterioration condition of the engine oil when Oil Control System remaining distance is zero. (two times ago)

--

DETERIORTN VL-OCS WRN 3

--

Indicates deterioration condition of the engine oil when Oil Control System remaining distance is zero. (three times ago)

--

CURRENT DETERIORATN VAN

--

Indicates deterioration condition of the engine oil.

--

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 B1

INCMP/CMPLT

Indicates DTC P219A self-diagnosis condition.

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

--

A/F SEN DIAG 1 (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(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 B1

ABSNT/PRSNT

Indicates DTC P219A self-diagnosis condition.

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

--

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.

--

Ignition timing 2

deg

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

NOTE: Indicates degree from BTDC (Before Top Dead Center) of compression stroke.

--

Di timing SOI multi inj step1

BTDC

These items are displayed but not used.

--

Di inj pules B1

msec

Indicates VCR control shaft 2 angle.

--