2001 NISSAN X-TRAIL turn signal

EC-36
[QR25(WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A°BTDC
During the following conditions, the ignition timing is revised by the
ECM according to the other data stored in the ECM.
●At starting
●During warm-up
●At idle
●At low battery voltage
●During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Air Conditioning Cut ControlEBS00M0E
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
●When the accelerator pedal is fully depressed.
●When cranking the engine.
●At high engine speeds.
●When the engine coolant temperature becomes excessively high.
●When operating power steering during low engine speed or low vehicle speed.
●When engine speed is excessively low.
●When refrigerant pressure is excessively low or high.
SEF742M
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner “ON” signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle valve opening angle
Crankshaft position sensor (POS) Engine speed
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor Vehicle speed

BASIC SERVICE PROCEDURE
EC-39
[QR25(WITH EURO-OBD)]
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EC
–Check ignition timing.
Accelerator Pedal Released Position LearningEBS00M0J
DESCRIPTION
“Accelerator Pedal Released Position Learning” is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON” and wait at least 2 seconds.
3. Turn ignition switch “OFF” wait at least 10 seconds.
4. Turn ignition switch “ON” and wait at least 2 seconds.
5. Turn ignition switch “OFF” wait at least 10 seconds.
Throttle Valve Closed Position LearningEBS00M0I
DESCRIPTION
“Throttle Valve Closed Position Learning” is an operation to learn the fully closed position of the throttle valve
by monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON” wait at least 10seconds.
3. Turn ignition switch “OFF” wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningEBS00M0K
DESCRIPTION
“Idle Air Volume Learning” is an operation to learn the idle air volume that keeps each engine within the spe-
cific range. It must be performed under any of the following conditions:
●Each time electric throttle control actuator or ECM is replaced.
●Idle speed or ignition timing is out of specification.
PREPARATION
Before performing “Idle Air Volume Learning”, make sure that all of the following conditions are satisfied.
SEF166Y
PBIB0514E

EC-78
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
1 - 6: The numbers refer to the order of inspection.Air Positive crankcase ventilation sys-
tem334444444 41EC-428
Incorrect idle speed adjustment 33 1111 1EC-73
Electric throttle control actuator 112332222 2 2EC-276
,
EC-278
,
EC-1018
IgnitionIncorrect ignition timing adjustment33111 11 1EC-73
Ignition circuit 11222 22 2EC-379
Main power supply and ground circuit 22333 33 23EC-116
Mass air flow sensor circuit 11222 22 2EC-138,
EC-999
Engine coolant temperature sensor circuit 11222322312EC-149
Throttle position sensor circuit 12 22222 2EC-886
Accelerator pedal position sensor circuit3212 2EC-893
Heated oxygen sensor 1 circuit 1232 22 2EC-163
,
EC-169
,
EC-178
,
EC-295
,
EC-301
Knock sensor circuit 2 2 3EC-222
Crankshaft position sensor (POS) circuit 2 2EC-227
Camshaft position sensor (PHASE) circuit 2 2EC-233
Vehicle speed signal circuit 2 3 3 3EC-250
Power steering pressure sensor circuit 2 3333EC-255
ECM 22333333333EC-260,
EC-267
Intake valve timing control solenoid valve cir-
cuit332 13223 3EC-125,
EC-271
VIAS control solenoid valve circuit 1
PNP switch circuit 3 3 3 3 3 3 3EC-345
Start signal circuit 2EC-401
Refrigerant pressure sensor circuit 2 3333 4EC-412
Electrical load signal circuit3333EC-416
Air conditioner circuit 223333333 3 2AT C - 3 3
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA

TROUBLE DIAGNOSIS
EC-79
[QR25(WITH EURO-OBD)]
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(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank
5
5FL-9
Fuel piping 5 5 5 5 5 5FL-3,EM-
32
Vapor lock—
Valve deposit
555555 5—
Poor fuel (Heavy weight gaso-
line, Low octane)—
Air Air duct
55555 5EM-14
Air cleanerEM-14
Air leakage from air duct
(Mass air flow sensor —electric
throttle control actuator)
5555EM-14
Electric throttle control actuatorEM-16
Air leakage from intake manifold/
Collector/GasketEM-16
Cranking Battery
111111 11SC-3
Alternator circuitSC-12
Starter circuit 3SC-20
Signal plate 6EM-73
PNP switch
4MT-12 or
AT- 11 5
Engine Cylinder head
55555 55 5EM-59
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-73
Piston
Piston ring
Connecting rod
Bearing
Crankshaft

EC-88
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
4PU/RHeated oxygen sen-
sor 2 heater[Engine is running]
●Engine speed is below 3,600 rpm after the follow-
ing conditions are met.
●Engine: after warming up
●Keeping the engine speed between 3,500 and
4,000 rpm for one minute and at idle for one
minute under no load.0 - 1.0V
[Ignition switch “ON”]
●Engine stopped
[Engine is running]
●Engine speed is above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
12 G/WCounter current
return[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
13 PEVAP canister purge
volume control sole-
noid valve[Engine is running]
●Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Engine speed is about 2,000 rpmApproximately 10V
18 R/Y MI[Ignition switch “ON”]0 - 1.0V
[Engine is running]
●Idle speedBATTERY VOLTAGE
(11 - 14V)
20 W/GECM relay
(Self shut-off)[Engine is running]
[Ignition switch “OFF”]
●For 3 seconds after turning ignition switch “OFF”0 - 1.0V
[Ignition switch “OFF”]
●3 seconds passed after turning ignition switch
“OFF”BATTERY VOLTAGE
(11 - 14V)
21
22
23
24BR
PU
L/R
GY/RIgnition signal No. 1
Ignition signal No. 2
Ignition signal No. 3
Ignition signal No. 4[Engine is running]
●Warm-up condition
●Idle speed0 - 0.1V
[Engine is running]
●Warm-up condition
●Engine speed is 2,000 rpm.0 - 0.2V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0520E
PBIB0521E
PBIB0522E

TROUBLE DIAGNOSIS
EC-89
[QR25(WITH EURO-OBD)]
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EC25 GY/LVIAS control sole-
noid valve[Engine is running]●Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Engine speed is above 5,000 rpm0 - 1.0V
26 L Air conditioner relay[Engine is running]
●Both A/C switch and blower switch are “ON”
(Compressor operates).0 - 1.0V
[Engine is running]
●A/C switch is “OFF”.BATTERY VOLTAGE
(11 - 14V)
27 LG/BCooling fan relay
(High)[Engine is running]
●Cooling fan is not operating
●Cooling fan is operating at low speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Cooling fan is operating at high speed0 - 1.0V
29 B/P Fuel pump relay[Ignition switch “ON”]
●For 1 seconds after turning ignition switch “ON”
[Engine is running]0 - 1.0V
[Ignition switch “ON”]
●More than 1 seconds after turning ignition switch
“ON”.BATTERY VOLTAGE
(11 - 14V)
30 PU/WAir conditioner cut
signal[Engine is running]
●Both A/C switch and blower switch are “ON”
(Compressor operates).Approximately 0V
[Engine is running]
●A/C switch is “ON”
(Compressor not operates).Approximately 4.6V
33 W/BCAN communication
line[Ignition switch “ON”]Approximately 2.6V
Output voltage varies with the
communication status.
34 L/RCAN communication
line[Ignition switch “ON”]Approximately 2.4V
Output voltage varies with the
communication status.
36 L/OR Tachometer signal[Engine is running]
●Warm-up condition
●Idle speed6 - 7V
[Engine is running]
●Engine speed is 2,500 rpm6 - 7V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0523E
PBIB0524E

EC-98
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
*1: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
×: Applicable CAL/LD VALUE [%]
●The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [°C]
or [°F]
●The engine coolant temperature at the moment a malfunction is detected is displayed.
S-FUEL TRIM-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
schedule.
L-FUEL TRIM-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.
ENGINE SPEED
[rpm]
●The engine speed at the moment a malfunction is detected is displayed.
VHCL SPEED [km/h]
or [mph]
●The vehicle speed 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 [°C]
or [°F]
●The intake air temperature at the moment a malfunction is detected is displayed. Freeze frame data
item*1Description
Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks
ENG SPEED [rpm]××
●Indicates the engine speed computed
from the signals of the crankshaft posi-
tion sensor (POS) and camshaft posi-
tion 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 [V]××
●The signal voltage of the mass air flow
sensor is displayed.●When the engine is stopped, a
certain value is indicated.
COOLAN TEMP/S
[°C] or [°F]××
●The engine coolant temperature (deter-
mined by the signal voltage of the
engine coolant temperature sensor) is
displayed.
●When the engine coolant tempera-
ture sensor is open or short-cir-
cuited, ECM enters fail-safe mode.
The engine coolant temperature
determined by the ECM is dis-
played.
HO2S1 (B1) [V]××
●The signal voltage of the heated oxygen
sensor 1 is displayed.
HO2S2 (B1) [V]××
●The signal voltage of the heated oxygen
sensor 2 is displayed.
HO2S1 MNTR (B1)
[RICH/LEAN]××
●Display of heated oxygen sensor 1 sig-
nal during air-fuel ratio feedback control:
RICH ... means the mixture became
“rich”, and control is being affected
toward a leaner mixture.
LEAN ... means the mixture became
“lean”, and control is being affected
toward a rich mixture.●After turning ON the ignition
switch, “RICH” is displayed until
air-fuel mixture ratio feedback
control begins.
●When the air-fuel ratio feedback is
clamped, the value just before the
clamping is displayed continu-
ously.

EC-102
[QR25(WITH 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 signals of the crankshaft posi-
tion sensor (POS) and camshaft position
sensor (PHASE).
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