TROUBLE DIAGNOSIS
EC-467
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EC
6.PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-450, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Ye s > > G O T O 7 .
No >> 1. Follow the instruction of “Idle Air Volume Learning”.
2. GO TO 4.
7.CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
OK or NG
OK >> GO TO 10.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the Following.
●Check camshaft position sensor (PHASE) and circuit. Refer to EC-1246 .
●Check crankshaft position sensor (POS) and circuit. Refer to EC-1240 .
OK or NG
OK >> GO TO 9.
NG >> 1. Repair or replace.
2. GO TO 4.
9.CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is the rarely the case.)
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to EC-456, "
NATS
(Nissan Anti-theft System)" .
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light.
OK or NG
OK >>INSPECTION END
NG >> GO TO 11.M/T: 700 ± 50 rpm
A/T: 700 ± 50 rpm (in “P” or “N” position)
M/T: 700 ± 50 rpm
A/T: 700 ± 50 rpm (in “P” or “N” position)
M/T: 15 ± 5° BTDC
A/T: 15 ± 5° BTDC (in “P” or “N” position)
EC-468
[QR25(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
11 . ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-449, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-449, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-450, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of “Idle Air Volume Learning”.
2. GO TO 4.
14. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.
15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
OK or NG
OK >>INSPECTION END
NG >> GO TO 16.M/T: 700 ± 50 rpm
A/T: 700 ± 50 rpm (in “P” or “N” position)
M/T: 700 ± 50 rpm
A/T: 700 ± 50 rpm (in “P” or “N” position)
M/T: 15 ± 5° BTDC
A/T: 15 ± 5° BTDC (in “P” or “N” position)
EC-482
[QR25(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
37 L/YCooling fan relay
(Low)[Engine is running]●Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Cooling fan is operating0 - 1.0V
40 P Stop lamp switch[Engine is running]
●Brake pedal releasedApproximately 0V
[Engine is running]
●Brake pedal depressedBATTERY VOLTAGE
(11 - 14V)
41 B/Y Start signal[Ignition switch “ON”]Approximately 0V
[Ignition switch “START”]9 - 14V
42 B/R Ignition switch[Ignition switch “OFF”]0V
[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
43 G/OR PNP switch[Ignition switch “ON”]
●Gear position is “P” or “N”.Approximately 0V
[Ignition switch “ON”]
●Except the above gear positionA/T model
BATTERY VOLTAGE
(11 - 14V)
M/T model
Approximately 5V
50 LG Data link connector[Ignition switch “ON”]
●CONSULT-II is disconnected.Approximately 5V
52 R/WElectrical load signal
(Rear window defog-
ger signal)[Ignition switch “ON”]
●Rear window defogger switch is “ON”BATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]
●Rear window defogger switch is “OFF”Approximately 0V
53 R/YElectrical load signal
(Headlamp signal)[Ignition switch “ON”]
●Lighting switch is “2ND” positionBATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]
●Lighting switch is “OFF”Approximately 0V
55 LG/BHeater fan switch sig-
nal[Ignition switch “ON”]
●Heater fan control switch is “ON”Approximately 0V
[Ignition switch “ON”]
●Heater fan control switch is “OFF”Approximately 5V
58 B Sensors' ground[Engine is running]
●Warm-up condition
●Idle speedApproximately 0V
59
60
106
108B/W
B/W
B/Y
B/YECM ground[Engine is running]
●Idle speedEngine ground TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
TROUBLE DIAGNOSIS
EC-491
[QR25(WITHOUT EURO-OBD)]
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EC
HO2S2 MNTR (B1)
[RICH/LEAN]×
●Display of heated oxygen sensor 2 sig-
nal:
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]××
●The vehicle speed computed from the
vehicle speed signal is displayed.
BATTERY VOLT
[V]××
●The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V]××
●The accelerator pedal position sensor
signal voltage is displayed.
ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××
●The throttle position sensor signal volt-
age is displayed.
THRTL SEN 2 [V]×
INT/A TEMP SE
[°C] or [°F]××
●The intake air temperature (determined
by the signal voltage of the intake air
temperature sensor) is indicated.
START SIGNAL
[ON/OFF]××
●Indicates [ON/OFF] condition from the
starter signal.●After starting the engine, [OFF] is
displayed regardless of the starter
signal.
CLSD THL POS
[ON/OFF]××
●Indicates idle position [ON/OFF] com-
puted by ECM according to the acceler-
ator pedal position sensor signal.
AIR COND SIG
[ON/OFF]××
●Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]××
●Indicates [ON/OFF] condition from the
park/neutral position (PNP) switch sig-
nal.
PW/ST SIGNAL
[ON/OFF]××
●[ON/OFF] condition of the power steer-
ing system (determined by the signal
voltage of the power steering pressure
sensor signal) is indicated.
LOAD SIGNAL
[ON/OFF]××
●Indicates [ON/OFF] condition from the
electrical load signal.
ON ... Rear window defogger switch is
ON and/or lighting switch is in 2nd posi-
tion.
OFF ... Both rear window defogger
switch and lighting switch are OFF.
IGNITION SW
[ON/OFF]××
●Indicates [ON/OFF] condition from igni-
tion switch.
HEATER FAN SW
[ON/OFF]×
●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 indi-
cated. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks
EC-494
[QR25(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
●Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]×
●Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS).
MAS A/F SE-B1 [V]××
●The signal voltage of the mass air flow
sensor specification is displayed.●When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]
●“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
●When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]×
●The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.●When engine is running specification
range is indicated.
●This data also includes the data for the
air-fuel ratio learning control.
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-II.If trouble symptom disappears, see
CHECK ITEM.
●Harness and connectors
●Fuel injectors
●Heated oxygen sensor 1
IGNITION TIM-
ING
●Engine: Return to the original
trouble condition
●Timing light: Set
●Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
●Perform “Idle Air Volume Learn-
ing”.
POWER BAL-
ANCE
●Engine: After warming up, idle
the engine.
●A/C switch “OFF”
●Shift lever “N”
●Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.
●Harness and connectors
●Compression
●Fuel injectors
●Power transistor
●Spark plugs
●Ignition coils
COOLING FAN
●Ignition switch: ON
●Turn the cooling fan “ON” and
“OFF” with CONSULT-II.Cooling fan moves and stops.
●Harness and connectors
●Cooling fan relay
●Cooling fan motor
ENG COOLANT
TEMP
●Engine: Return to the original
trouble condition
●Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
●Harness and connectors
●Engine coolant temperature sen-
sor
●Fuel injectors
FUEL PUMP
RELAY
●Ignition switch: ON (Engine
stopped)
●Turn the fuel pump relay “ON”
and “OFF” using CONSULT-II
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.●Harness and connectors
●Fuel pump relay
EC-496
[QR25(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
CONSULT-II Reference Value in Data Monitor
EBS00NEJ
Remarks:
● Specification data are reference values.
● Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data in
spite of the ignition timing not being adjusted to the specification data. This IGN TIMING monitors the data calculated by the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
PBIB0197E
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED
●Run engine and compare CONSULT-II value with the tachometer indica-
tion.Almost the same speed as the
tachometer indication.
MAS A/F SE-B1
●Engine: After warming up
●Air conditioner switch: OFF
●Shift lever: N
●No-loadIdle Approx. 1.0 - 1.5V
2,500 rpm Approx. 1.6 - 2.0V
B/FUEL SCHDL
●Engine: After warming up
●Shift lever: N
●Air conditioner switch: OFF
●No-loadIdle 2.5 - 3.5 msec
2,000 rpm 2.5 - 3.5 msec
A/F ALPHA-B1
●Engine: After warming upMaintaining engine speed at 2,000
rpm54% - 155%
COOLAN TEMP/S
●Engine: After warming up More than 70°C (158°F)
HO2S1 (B1)
●Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S2 (B1)
●Engine: After warming up
●Keeping the engine speed at
between 3,500 to 4,000 rpm for
one minute and at idle for one
minute under no loadRevving engine from idle up to 3,000
rpm quickly0 - 0.3V ←→ Approx. 0.6 - 1.0V
TROUBLE DIAGNOSIS
EC-497
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EC
HO2S1 MNTR (B1)●Engine: After warming upMaintaining engine speed at 2,000
rpmLEAN←→ RICH
Changes more than 5 times dur-
ing 10 seconds.
HO2S2 MNTR (B1)
●Engine: After warming up
●Keeping the engine speed at
between 3,500 to 4,000 rpm for
one minute and at idle for one
minute under no loadRevving engine from idle up to 3,000
rpm quicklyLEAN←→ RICH
VEH SPEED SE
●Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as the
speedometer indication.
BATTERY VOLT
●Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN1
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.41 - 0.72V
Accelerator pedal: Fully depressed 3.2 - 4.9V
ACCEL SEN2*
2●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.15 - 0.98V
Accelerator pedal: Fully depressed 2.98 - 4.9V
THRTL SEN1
THRTL SEN2*
2
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released More than 0.36V
●Shift lever:
D (A/T model)
1st (M/T model)Accelerator pedal: Fully depressed Less than 4.75V
START SIGNAL
●Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS
●Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG
●Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
P/N POSI SW
●Ignition switch: ONShift lever:
P or N (A/T model)
Neutral (M/T model)ON
Shift lever: Except above OFF
PW/ST SIGNAL
●Engine: After warming up, idle
the engineSteering wheel is in neutral position.
(Forward direction)OFF
Steering wheel is turned. ON
LOAD SIGNAL
●Ignition switch: ONRear window defogger switch is ON
and/or lighting switch is in 2nd.ON
Rear window defogger switch is OFF
and lighting switch is OFF.OFF
IGNITION SW
●Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW
●Engine: After warming up, idle
the engineHeater fan is operating. ON
Heater fan is not operating OFF
BRAKE SW
●Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
INJ PULSE-B1
●Engine: After warming up
●Shift lever: N
●Air conditioner switch: OFF
●No-loadIdle 2.0 - 3.0 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING
●Engine: After warming up
●Shift lever: N
●Air conditioner switch: OFF
●No-loadIdleMT: 12° - 16° BTDC
AT: 1 4° - 18° BTDC
2,000 rpm 25° - 45° BTDC MONITOR ITEM CONDITION SPECIFICATION
EC-502
[QR25(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
PFP:00031
DescriptionEBS00NEL
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MI.
The SP value will be displayed for the following three items:
●B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)
●A/F ALPHA-B1 (The mean value of air-fuel ratio feedback correction factor per cycle)
●MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionEBS00NEM
●Vehicle driven distance: More than 5,000 km (3,017 miles)
●Barometric pressure: 98.3 - 104.3 kPa (0.983 - 1.043 bar, 1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)
●Atmospheric temperature: 20 - 30°C (68 - 86°F)
●Engine coolant temperature: 75 - 95°C (167 - 203°F)
●Transmission: Warmed-up*1
●Electrical load: Not applied*2
●Engine speed: Idle
*1: For A/T models, after the engine is warmed up to normal operating temperature, drive vehicle until “FLUID
TEMP SE” (A/T fluid temperature sensor signal) indicates more than 60°C (140°F).
For M/T models, after the engine is warmed up to normal operating temperature, drive vehicle for 5 minutes.
*2: Rear window defogger switch, air conditioner switch, lighting switch are “OFF”. Steering wheel is straight
ahead.
Inspection ProcedureEBS00NEN
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-465, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1” and “MAS A/F SE-
B1” in “DATA MONITOR (SPEC)” mode with CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-503, "
Diagnostic Procedure" .
SEF601Z