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Home >> Infiniti >> 2021 >> Q50 Pure, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (1 Of 4) >> 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

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.

TURBO BST SEN

V

  • The turbocharger boost sensor signal voltage is displayed.

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.
  • When engine is running, specification range is indicated in "SPEC".

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)

TC/SC SPEED B1

RPM

  • The turbocharger revolution speed (determined by the signal voltage of the turbocharger speed sensor) is displayed.

TC/SC SPEED B2

EXH/V TIM B1

deg. CA

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

EXH/V TIM B2

W/GATE V CLSD LEARN B2

INCMP/CMPLT

Displays "full close position learning" experience of wastegate actuator.

  • INCMP: Learning is incomplete. There is no memory of the full close position voltage in the ECM.
  • CMPLT: Learning is complete. Full close position voltage is memory in the ECM.

W/GATE V CLSD LEARN B1

W/G ACTUATOR POSITION B1

m

  • Indicates real stroke position of turbocharger wastegate actuator. The value is calculated by ECM based on the difference voltage between position sensor output and valve close position.

W/G ACTUATOR POSITION B2

RADIATOR COOLANT TEMP

deg. C

  • The radiator coolant temperature (determined by the signal voltage of the radiator coolant temperature sensor) is displayed.

Ignition timing

deg

x

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.

Fuel injection timing

deg

  • Indicates the fuel injection timing computed by ECM according to the input signals.
    NOTE: Indicates degree from BTDC (Before Top Dead Center) of intake stroke.

Charge air cooler coolant temp

deg

  • The charge air cooler coolant temperature (determined by the signal voltage of the charge air cooler coolant temperature sensor) is displayed.

FAN DUTY

%

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

AC EVA TEMP

deg. C or deg. F

  • Indicates A/C evaporator temperature sent from "unified meter and A/C amp".

AC EVA TARGET

deg. C or deg. F

  • Indicates target A/C evaporator temperature sent from "unified meter and A/C amp".

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.

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.

THRTL STK CNT B2

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

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".

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

FUEL INJ B1

msec

  • ECM-calculated injection pulse width of the fuel injector on the Bank 1 side.

FUEL INJ B2

IDLE FUEL PRES MIN

MPa

  • Lower limit of fuel pressure at idle state.

IDLE FUEL PRES MAX

  • Upper limit of fuel pressure at idle state.

I/P PULLEY 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.

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

mV

  • The signal voltage of battery current sensor is displayed.

MILEAGE FOR EONV

km

  • Mileage counter for EONV upper byte 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

TP SEN 1-B2

mV

  • The throttle position sensor signal voltage is displayed.
  • TP SEN 2-B2 signal is converted by ECM internally. Thus, they differs from ECM terminal voltage signal.

TP SEN 2-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)

Hz

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

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 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 UP B2

count

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

A/F-S ATMSPHRC CRCT UP B1

count

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

EXHAUST GAS TEMP SEN 1 B1

V

  • The signal voltage of exhaust gas temperature sensor is displayed.

EXHAUST GAS TEMP SEN 1 B2

Mass air flow sensor B2 (Hz)

Hz

  • The signal frequency of the mass air flow sensor bank 2 is displayed.

W/G ACTUATOR POSI SEN B1

V

  • Indicates position sensor output voltage of turbocharger wastegate actuator.

W/G ACTUATOR POSI SEN B2

ENGINE COOLANT B/V POSI

deg

  • The Multi-way Control Valve position detected by the position sensor is displayed.

Electric water pump 1 duty

%

  • The control condition of the charge air cooler cooling electric water pump (determined by ECM according to the input signals) is indicated.

Electric water pump 2 duty

TOTAL DISTANC - OCS RST 1

km

  • The Multi-way Control Valve position detected by the position sensor is displayed.

TOTAL DISTANC - OCS RST 2

km

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

TOTAL DISTANC - OCS RST 3

km

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

DETERIORTN VL - OCS RST 1

--

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

DETERIORTN VL - OCS RST 2

--

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

DETERIORTN VL - OCS RST 3

--

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

TOTAL DISTANC - OCS WRN 1

km

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

TOTAL DISTANC - OCS WRN 2

km

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

TOTAL DISTANC - 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 VAL

--

  • Indicates deterioration condition of the engine oil.

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

--

  • 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)

DIST SW

On/Off

  • Indicates [On/Off] condition from DISTANCE switch signal.

BRAKE SW1

On/Off

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

BRAKE SW2

On/Off

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

SET SW

On/Off

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

RESUME/ACC SW

On/Off

  • Indicates [On/Off] condition from RESUME/ACCELERATE 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 CVT O/D according to the input signal from the TCM.

For M/T models, always "OFF" is displayed.

AT OD MONITOR

On/Off

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

For M/T models, always "OFF" is displayed.

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

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

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.

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