Content .. 483 484 485 486 ..

Infiniti G37 Coupe. Manual - part 485

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-121

< FUNCTION DIAGNOSIS >

[VQ37VHR]

Item

DIAGNOSTIC TEST MODE

WORK

SUPPORT

SELF-DIAGNOSTIC

RESULTS

DATA

MONI-

TOR

ACTIVE

TEST

DTC & SRT

CONFIRMATION

DTC*1

FREEZE

FRAME
DATA*2

SRT STA-

TUS

DTC

WORK

SUP-

PORT

ENGINE CONTROL

MPONENT P

ARTS

INP

Crankshaft position sensor (POS)

Camshaft position sensor (PHASE)

Mass air flow sensor

Engine coolant temperature sensor

Engine oil temperature sensor

Air fuel ratio (A/F) sensor 1

Heated oxygen sensor 2

Wheel sensor

Accelerator pedal position sensor

Throttle position sensor

Fuel tank temperature sensor

EVAP control system pressure sensor

Intake air temperature sensor

Knock sensor

Refrigerant pressure sensor

Closed throttle position switch (accel-
erator pedal position sensor signal)

Air conditioner switch

Park/neutral position (PNP) switch

Stop lamp switch

Power steering pressure sensor

Battery voltage

Load signal

Fuel level sensor

Battery current sensor

ICC steering switch

ASCD steering switch

ICC brake switch

ASCD brake switch

VVEL control shaft position sensor

Manifold absolute pressure (MAP)
sensor

Brake booster pressure sensor

EC-122

< FUNCTION DIAGNOSIS >

[VQ37VHR]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

: Applicable

*1: This item includes 1st trip DTCs.

*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-III screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to

EC-107, "Diagnosis Description"

*3: Always “CMPLT” is displayed.

WORK SUPPORT MODE

Work Item

ENGINE CONTROL COMPON

T P

Fuel injector

Power transistor (Ignition timing)

Throttle control motor relay

Throttle control motor

EVAP canister purge volume control
solenoid valve

Air conditioner relay

Fuel pump relay

Cooling fan relay

Air fuel ratio (A/F) sensor 1 heater

Heated oxygen sensor 2 heater

EVAP canister vent control valve

Intake valve timing control solenoid
valve

VVEL actuator motor relay

VVEL actuator motor

Alternator

Calculated load value

Item

DIAGNOSTIC TEST MODE

WORK

SUPPORT

SELF-DIAGNOSTIC

RESULTS

DATA

MONI-

TOR

ACTIVE

TEST

DTC & SRT

CONFIRMATION

DTC*1

FREEZE

FRAME
DATA*2

SRT STA-

TUS

DTC

WORK

SUP-

PORT

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-123

< FUNCTION DIAGNOSIS >

[VQ37VHR]

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

SELF-DIAG RESULTS MODE

Self Diagnostic Item

Regarding items of DTC and 1st trip DTC, refer to

EC-552, "DTC Index"

Freeze Frame Data and 1st Trip Freeze Frame Data

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.
• IGN SW ON
• ENGINE NOT RUNNING
• AMBIENT TEMPERATURE IS ABOVE 0

C (32

F).

• NO VACUUM AND NO HIGH PRESSURE IN EVAP SYS-

TEM

• FUEL TANK TEMP. IS MORE THAN 0

C (32

F).

• WITHIN 10 MINUTES AFTER STARTING “EVAP SYS-

TEM CLOSE”

• WHEN TRYING TO EXECUTE “EVAP SYSTEM CLOSE”

UNDER THE CONDITION EXCEPT ABOVE, CONSULT-
III WILL DISCONTINUE IT AND DISPLAY APPROPRI-
ATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-III MAY DIS-
PLAY “BATTERY VOLTAGE IS LOW. CHARGE BAT-
TERY”, EVEN IN USING CHARGED BATTERY.

When detecting EVAP vapor leak
point of EVAP system

FUEL PRESSURE RELEASE

• FUEL PUMP WILL STOP BY TOUCHING “START” DUR-

ING IDLING.
CRANK A FEW TIMES AFTER ENGINE STALLS.

When releasing fuel pressure from
fuel line

SELF-LEARNING CONT

• THE COEFFICIENT OF SELF-LEARNING CONTROL

MIXTURE RATIO RETURNS TO THE ORIGINAL COEF-
FICIENT.

When clearing mixture ratio self-
learning value

TARGET IDLE RPM ADJ*

• IDLE CONDITION

When setting target idle speed

TARGET IGN TIM ADJ*

• IDLE CONDITION

When adjusting target ignition tim-
ing

VIN REGISTRATION

• IN THIS MODE, VIN IS REGISTERED IN ECM.

When registering VIN in ECM

VVEL POS SEN ADJ PREP

• USE THIS ITEM ONLY WHEN REPLACING VVEL ACTU-

ATOR SUB ASSEMBLY.

• IGNITION ON AND ENGINE STOPPED.

When adjusting VVEL control
shaft position sensor

Freeze frame data

item*

Description

DIAG TROUBLE
CODE
[PXXXX]

• The engine control component part/control system has a trouble code, it is displayed as PXXXX. (Refer to

EC-552, "DTC Index"

CAL/LD VALUE [%]

• The calculated load value at the moment a malfunction is detected is displayed.

COOLANT TEMP [

or [

• The engine coolant temperature at the moment a malfunction is detected is displayed.

L-FUEL TRM-B1 [%]

• “Long-term fuel trim” at the moment a malfunction is detected is displayed.
• The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule than

short-term fuel trim.

L-FUEL TRM-B2 [%]

S-FUEL TRM-B1 [%]

• “Short-term fuel trim” at the moment a malfunction is detected is displayed.
• The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel sched-

ule.

S-FUEL TRM-B2 [%]

E C - 1 2 4

< FUNCTION DIAGNOSIS >

[VQ37VHR]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

*: The items are the same as those of 1st trip freeze frame data.

DATA MONITOR MODE

Monitored Item

: Applicable

ENGINE SPEED [rpm]

• The engine speed at the moment a malfunction is detected is displayed

VEHICL SPEED
[km/h] or [mph]

• The vehicle speed at the moment a malfunction is detected is displayed

ABSOL TH·P/S [%]

• The throttle valve opening angle at the moment a malfunction is detected is displayed

B/FUEL SCHDL
[msec]

• The base fuel schedule at the moment a malfunction is detected is displayed

INT/A TEMP SE [

or [

• The intake air temperature at the moment a malfunction is detected is displayed

FUEL SYS-B1

• “Fuel injection system status” at the moment a malfunction is detected is displayed.
• One mode in the following is displayed.

Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop

FUEL SYS-B2

Freeze frame data

item*

Description

Monitored item

Unit

Description

Remarks

ENG SPEED

rpm

• 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

• 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”.

MAS A/F SE-B2

B/FUEL SCHDL

msec

• “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 cor-

rection 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

COOLAN TEMP/S

C or

• The engine coolant temperature (determined by

the signal voltage of the engine coolant tempera-
ture sensor) is displayed.

• When the engine coolant temperature

sensor is open or short-circuited,
ECM enters fail-safe mode. The en-
gine coolant temperature determined
by the ECM is displayed.

A/F SEN1 (B1)

• The A/F signal computed from the input signal of

the air fuel ratio (A/F) sensor 1 is displayed.

A/F SEN1 (B2)

HO2S2 (B1)

• The signal voltage of the heated oxygen sensor 2

is displayed.

HO2S2 (B2)

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.

HO2S2 MNTR (B2)

VHCL SPEED SE

km/h or mph

• The vehicle speed computed from the vehicle

speed signal sent from combination meter is dis-
played.

Content .. 483 484 485 486 ..