Nissan Sentra. Manual - part 344

EC-72

< SYSTEM DESCRIPTION >

[MRA8DE]

DIAGNOSIS SYSTEM (ECM)

A/F ADJ-B1

—

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

TUMBLE POS 
SEN

V

• The intake manifold runner control valve 

position sensor signal voltage is dis-
played.

P/N POSI SW

ON/OFF

×

×

Indicates [ON/OFF] condition from the park/
neutral position (PNP) signal.

INT/A TEMP SE

°C or °F

×

×

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

AC PRESS SEN

V

The signal voltage from the refrigerant pres-
sure 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 diag-

nosis.
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: EVAP leak diagnosis has been ready 
condition.
OFF: EVAP leak diagnosis has not been 
ready condition.

BAT TEMP SEN

V

The signal voltage of battery temperature 
sensor is displayed.

THRTL STK 
CNT B1

—

—

A/F SEN1 
DIAG1(B1)

INCMP/CM-

PLT

• Indicates DTC P015A or P015B self-diag-

nosis condition.

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

A/F SEN1 
DIAG2 (B1)

INCMP/CM-

PLT

Indicates DTC P014C or P014D self-diag-
nosis 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/CM-

PLT

• Indicates DTC P0139 self-diagnosis (de-

layed response) condition.

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

Monitored item

Unit

Monitor Item Selection

Description

Remarks

ECU INPUT 

SIGNALS

MAIN 

SIGNALS

DIAGNOSIS SYSTEM (ECM)

EC-73

< SYSTEM DESCRIPTION >

[MRA8DE]

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WORK SUPPORT MODE

Work Item

HO2 S2 DIAG2 
(B1)

INCMP/CM-

PLT

Indicates DTC P0139 self-diagnosis (slow 
response) condition.
• INCMP: Self-diagnosis is incomplete.
• CMPLT: Self-diagnosis is complete.

EOP SENSOR

mV

The signal voltage of EOP sensor is dis-
played.

SPORT MODE 
SWITCH

On/Off

Displays the reception status of the sport 
mode switch signal received through CAN 
communication.

ECO MODE 
SWITCH

ON/OFF

×

Displays the reception status of the ECO 
mode switch signal received through CAN 
communication.

A/F-S ATM-
SPHRC 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 sig-
nal transmitted while driving under atmo-
spheric pressure.

A/F-S ATM-
SPHRC CRCT 
UP B1

count

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

Monitored item

Unit

Monitor Item Selection

Description

Remarks

ECU INPUT 

SIGNALS

MAIN 

SIGNALS

Work item

Condition

Usage

IDLE AIR VOL LEARN

The idle air volume that keeps the engine within the specified 
range is memorized in ECM.

When learning the idle air volume

EVAP SYSTEM CLOSE

Close the EVAP canister vent control valve in order to make 
EVAP system close under the following conditions.
• Ignition switch ON
• Engine not running
• Ambient temperature is above 0

°C (32°F).

• No vacuum and no high pressure in EVAP system
• Fuel tank temp is more than 0

°C (32°F).

• Within 10 minutes after starting “EVAP SYSTEM CLOSE”
• When trying to execute “EVAP SYSTEM CLOSE” under 

the condition except above, CONSULT will discontinue it 
and display appropriate instruction.
NOTE:
When starting engine, CONSULT may display “BAT-
TERY VOLTAGE IS LOW. CHARGE BATTERY”, even in 
when using a charged battery.

When detecting EVAP vapor leak 
in the EVAP system

FUEL PRESSURE RELEASE

Crank a few times after engine stalls.

When releasing fuel pressure from 
fuel line

TARGET IDLE RPM ADJ*

Idle condition

When setting target idle speed

VIN REGISTRATION

• In this mode, VIN is registered in ECM.

When registering VIN in ECM

SELF-LEARNING CONT

The coefficient of self-learning control mixture ratio returns to 
the original coefficient.

When clearing mixture ratio self-
learning value

TARGET IGN TIM ADJ*

Idle condition

When adjusting target ignition tim-
ing

CLSD THL POS LEARN

• Ignition on and engine stopped.

When learning the throttle valve 
closed position

EC-74

< SYSTEM DESCRIPTION >

[MRA8DE]

DIAGNOSIS SYSTEM (ECM)

*: This function is not necessary in the usual service procedure.

ACTIVE TEST MODE

Test Item

SAVING DATA FOR REPLC CPU

In this mode, save data that is in ECM.

When ECM is replaced.

WRITING DATA FOR REPLC CPU

In this mode, write data stored by “SAVE DATA FOR CPU 
REPLC” in work support mode to ECM.

When ECM is replaced.

Work item

Condition

Usage

Test item

Condition

Judgement

Check item (Remedy)

FUEL INJECTION

• Engine: Return to the original 

trouble condition

• Change the amount of fuel injec-

tion using CONSULT.

If trouble symptom disappears, see 
Check item.

• Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1

ENG COOLANT 
TEMP

• Engine: Return to the original 

trouble condition

• Change the engine coolant tem-

perature using CONSULT.

If trouble symptom disappears, see 
Check item.

• Harness and connectors
• Engine coolant temperature sen-

sor

• Fuel injector

PURG VOL CONT/V

• Engine: After warming up, run 

engine at 1,500 rpm.

• Change the EVAP canister 

purge volume control solenoid 
valve opening percent using 
CONSULT.

Engine speed changes according 
to the opening percent.

• Harness and connectors
• Solenoid valve

FUEL/T TEMP SEN

• Change the fuel tank temperature using CONSULT.

COOLING FAN

*

• Ignition switch: ON
• Select LOW or HIGH on CON-

SULT screen.

Cooling fan operates at low speed 
or high speed.

• Harness and connectors
• Cooling fan motor
• Cooling fan relay
• IPDM E/R

ALTERNATOR DUTY

• Ignition switch: ON
• Change duty ratio using CON-

SULT.

Battery voltage changes.

• Harness and connectors
• Alternator
• IPDM E/R

FUEL PUMP RELAY

• Ignition switch: ON (Engine 

stopped)

• Turn the fuel pump relay “ON” 

and “OFF” using CONSULT and 
listen to operating sound.

Fuel pump relay makes the operat-
ing sound.

• Harness and connectors
• Fuel  pump  relay

VIAS S/V-1

• Ignition switch: ON (Engine 

stopped)

• Turn Intake Manifold Tuning 

(IMT) Valve “ON” and “OFF” us-
ing CONSULT and listen to oper-
ating sound.

IMT valve motor makes an operat-
ing sound.

• Harness and connectors
• IMT valve motor

TUMBLE CONTROL 
VALVE

• Ignition switch: ON
• Turn intake manifold runner con-

trol valve “ON” and “OFF” using 
CONSULT and listen to operat-
ing sound.

Intake Manifold Runner control 
valve motor makes an operating 
sound.

• Harness and connectors
• Intake Manifold Runner control 

valve motor

IGNITION TIMING

• Engine: Return to the original 

trouble condition

• Timing light: Set
• Retard the ignition timing using 

CONSULT.

If trouble symptom disappears, see 
Check item.

Perform Idle Air Volume Learning.

DIAGNOSIS SYSTEM (ECM)

EC-75

< SYSTEM DESCRIPTION >

[MRA8DE]

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*: Leaving cooling fan OFF with CONSULT while engine is running may cause the engine to overheat.

DTC WORK SUPPORT MODE

SRT & P-DTC MODE

SRT STATUS Mode

• For items whose SRT codes are set, “CMPLT” is displayed on the CONSULT screen; for items whose SRT

codes are not set, “INCMP” is displayed.

• “SRT STATUS” provides the presence or absence of permanent DTCs stored in ECM memory.

PERMANENT DTC STATUS Mode

How to display permanent DTC status

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

4. Turn ignition switch ON.

5. Select “PERMANENT DTC STATUS” in “DTC & SRT CONFIRMATION” mode with CONSULT.

NOTE:

Permanent DTCs stored in ECM memory are displayed on the CONSULT screen to show if a driving pat-

tern required for erasing permanent DTCs is complete (CMPLT) or incomplete (INCMP).

CAUTION:

POWER BALANCE

• Engine: After warming up, idle 

the engine.

• A/C switch OFF
• Selector lever: P or N (CVT mod-

els)

• Shifter lever: Neutral (M/T mod-

els)

• Cut off each fuel injector signal 

one at a time using CONSULT.

Engine runs rough or stops.

• Harness and connectors
• Compression
• Fuel injector
• Power transistor
• Spark plug
• Ignition coil

VENT CONTROL/V

• Ignition switch: ON (Engine 

stopped)

• Turn solenoid valve “ON” and 

“OFF” using CONSULT and lis-
ten to operating sound.

Solenoid valve makes an operating 
sound.

• Harness and connectors
• Solenoid valve

INT V/T ASSIGN AN-
GLE

• Engine: Return to the original 

trouble condition

• Change intake valve timing us-

ing CONSULT.

If trouble symptom disappears, see 
CHECK ITEM.

• Harness and connectors
• Intake valve timing control sole-

noid valve

EXH V/T ASSIGN 
ANGLE

• Engine: Return to the original 

trouble condition

• Change exhaust valve timing us-

ing CONSULT.

If trouble symptom disappears, see 
CHECK ITEM.

• Harness and connectors
• Exhaust valve timing control sole-

noid valve

Test item

Condition

Judgement

Check item (Remedy)

Test mode

Test item

Corresponding DTC No.

Reference page

A/F SEN1

A/F SEN1 (B1) P1276

P0130

EC-210

EVAPORATIVE SYS-
TEM

PURG FLOW P0441

P0441

EC-288

PURG VOL CN/V P1444

P0443

EC-293

HO2S2

HO2S2 (B1) P1146

P0138

EC-225

HO2S2 (B1) P1147

P0137

EC-220

HO2S2 (B1) P0139

P0139

EC-232