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Home >> Nissan-Datsun >> 2014 >> Altima Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Introduction) (Qr25DE) >> System Description >> Diagnosis System (ECM) >> Diagnosis Description >> 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
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.
MAS A/F SE-B1 V x x
  • The signal voltage of the mass air flow sensor is displayed.
  • When the engine is stopped, a certain value is indicated.
  • When engine is running, specification range is indicated in "SPEC".
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 %    
  • 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.
  • When engine is running, specification range is indicated in "SPEC".
  • This data also includes the data for the air-fuel ratio learning control.
COOLAN TEMP/S °C or °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 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.
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.
  
ACCEL SEN 1 V    
  • 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    
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 x x
FUEL T/TMP SE °C or °F    
  • The fuel temperature (determined by the signal voltage of the fuel tank temperature sensor) is displayed.
  
EVAP SYS PRES V    
  • 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    
  • 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 sent from EPS control unit) 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    
  • 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 signals.
  • When the engine is stopped, a certain computed value is indicated.
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) °CA    
  • Indicates [°CA] of intake camshaft advance angle.
  
EXH/V TIM B1 °CA    
  • Indicates [°CA] of exhaust camshaft advance angle.
  
INT/V SOL(B1) %    
  • 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.
  
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
  
VIAS S/V-1 On/Off    
  • The control condition of the intake manifold tuning 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.
  
COOLING FAN Hi/Mid/Low/Off    
  • Indicates the condition of the cooling fan (determined by ECM according to the input signals).
    • 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.
  
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.
  
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.
  
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 °C or °F    
  • The engine oil temperature (determined by the signal voltage of the engine oil temperature sensor) is displayed.
  
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.
  
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.
  
MAIN SW On/Off    
  • Indicates [ON/OFF] condition from MAIN switch signal.
  
CANCEL SW On/Off    
  • Indicates [ON/OFF] condition from CANCEL switch signal.
  
RESUME/ACC SW On/Off    
  • Indicates [ON/OFF] condition from RESUME/ACCELERATE switch signal.
  
SET SW On/Off    
  • Indicates [ON/OFF] condition from SET/COAST 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.
  
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.
  
ALT DUTY %    
  • Indicates the duty ratio of the power generation command value. The ratio is caluculated by ECM based on the battery current sensor signal.
  
BAT CUR SEN mV    
  • 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.
  
TUMBLE POS SEN V    
  • The intake manifold runner control valve position sensor signal voltage is displayed.
  
P/N POSI SW On/Off x x
  • Indicates [ON/OFF] condition from the park/neutral position (PNP) signal.
  
INT/A TEMP SE °C or °F x x
  • The intake air temperature (determined by the signal voltage of the intake air temperature sensor) is indicated.
  
AC PRESS SEN V    
  • The signal voltage from the refrigerant pressure sensor 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.
  
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    
  • The signal voltage of battery temperature sensor is displayed.
  
EOP SENSOR mV    
  • The signal voltage of battery temperature sensor is displayed.
  
THRTL STK CNT B1(1) -     -  
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(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(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 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 (B1) INCMP/CMPLT    
  • Indicates DTC P0139 self-diagnosis (slow response) condition.
    • INCMP: Self-diagnosis is incomplete.
    • CMPLT: Self-diagnosis is complete.
  
SYSTEM 1 DIAGNOSIS A B1 INCMP/CMPLT    
  • Indicates DTC P117A self-diagnosis condition.
    • INCMP: Self-diagnosis is incomplete.
    • CMPLT: Self-diagnosis is complete.
  
SYSTEM 1 DIAGNOSIS B B1 ABSNT/PRSNT    
  • Indicates DTC P117A self-diagnosis condition.
    • ABSNT: Self-diagnosis standby
    • PRSNT: Under self-diagnosis
  
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 B1 count     Displays the number of updates of the A/F sensor atmospheric correction factor.  
(1) 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.
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