Nissan Pathfinder. Manual - part 441
EC-70
< SYSTEM DESCRIPTION >
[VQ35DE]
DIAGNOSIS SYSTEM (ECM)
*: This function is not necessary in the usual service procedure.
ACTIVE TEST MODE
Test Item
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 temperature is more than 0
°C (32°F).
• Within 10 minutes after starting “EVAP SYSTEM
CLOSE”
• When trying to execute “EVAP SYSTEM CLOSE” un-
der the condition except above, CONSULT will discon-
tinue it and display appropriate instruction.
NOTE:
When starting engine, CONSULT may display
“BATTERY VOLTAGE IS LOW. CHARGE BAT-
TERY”, even in using charged battery.
When detecting EVAP vapor leakage in the
EVAP system
FUEL PRESSURE RE-
LEASE
Fuel pump will stop by touching “START” during 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 re-
turns to the original coefficient.
When clearing mixture ratio self-learning value
TARGET IGN TIM ADJ*
Idle condition
When adjusting target ignition timing
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
CLSD THL POS LEARN
Ignition on and engine stopped.
When learning the throttle valve closed position
SAVING DATA FOR RE-
PLC CPU
In this mode, save data that is in ECM.
When ECM is replaced.
WRITING DATA FOR RE-
PLC CPU
In this mode, write data stored by “SAVE DATA FOR
CPU REPLC” in work support mode to ECM.
When ECM is replaced.
TEST ITEM
CONDITION
JUDGMENT
CHECK ITEM (REMEDY)
FUEL INJEC-
TION
• Engine: Return to the original
non-standard condition
• Change the amount of fuel injec-
tion using CONSULT.
If malfunctioning symptom disap-
pears, see CHECK ITEM.
• Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1
ENG COOLANT
TEMP
• Engine: Return to the original
non-standard condition
• Change the engine coolant tem-
perature using CONSULT.
If malfunctioning symptom disap-
pears, see CHECK ITEM.
• Harness and connectors
• Engine coolant temperature sen-
sor
• Fuel injector
PURG VOL
CONT/V
• Engine: After warming up, run en-
gine at 1,500 rpm.
• Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT.
Engine speed changes according to
the opening percent.
• Harness and connectors
• Solenoid valve
FUEL/T TEMP
SEN
• Change the fuel tank temperature using CONSULT.