Nissan Frontier D40. Manual - part 346
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-75
< FUNCTION DIAGNOSIS >
[QR25DE]
C
D
E
F
G
H
I
J
K
L
M
A
EC
N
P
O
ACTIVE TEST MODE
Test Item
A/F ADJ-B1
• Indicates the correction factor stored in
ECM.
The factor is calculated from the differ-
ence between the target air-fuel ratio
stored in ECM and the air-fuel ratio calcu-
lated form A/F sensor 1 signal.
BAT CUR SEN [mV]
• The signal voltage of battery current sen-
sor is displayed.
ALT DUTY SIG
[ON/OFF]
• The control condition of the power gener-
ation 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
• indicates the engine speed computed
from the input speed sensor signal.
Monitored item [Unit]
ECM
INPUT
SIG-
NALS
MAIN
SIG-
NALS
Description
Remarks
TEST ITEM
CONDITION
JUDGEMENT
CHECK ITEM (REMEDY)
FUEL INJEC-
TION
• Engine: Return to the original
trouble condition
• Change the amount of fuel injec-
tion using CONSULT-III.
If trouble symptom disappears, see
CHECK ITEM.
• Harness and connectors
• Fuel injector
• A/F sensor 1
IGNITION TIM-
ING
• Engine: Return to the original
trouble condition
• Timing light: Set
• Retard the ignition timing using
CONSULT-III.
If trouble symptom disappears, see
CHECK ITEM.
• Perform Idle Air Volume Learning.
POWER BAL-
ANCE
• Engine: After warming up, idle the
engine.
• A/C switch OFF
• Shift lever: P or N (A/T), Neutral
(M/T)
• Cut off each injector signal one at
a time using CONSULT-III.
Engine runs rough or dies.
• Harness and connectors
• Compression
• Fuel injector
• Power transistor
• Spark plug
• Ignition coil
ENG COOLANT
TEMP
• Engine: Return to the original
trouble condition
• Change the engine coolant tem-
perature using CONSULT-III.
If trouble symptom disappears, see
CHECK ITEM.
• Harness and connectors
• Engine coolant temperature sen-
sor
• Fuel injector
FUEL PUMP RE-
LAY
• Ignition switch: ON
(Engine stopped)
• Turn the fuel pump relay ON and
OFF using CONSULT-III and lis-
ten to operating sound.
Fuel pump relay makes the operat-
ing sound.
• Harness and connectors
• Fuel pump relay
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-III.
Engine speed changes according to
the opening percent.
• Harness and connectors
• Solenoid valve
FUEL/T TEMP
SEN
• Change the fuel tank temperature using CONSULT-III.