relay NISSAN X-TRAIL 2001 Service User Guide

ENGINE CONTROL SYSTEM
EC-33
[QR25(WITH EURO-OBD)]
C
D
E
F
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MA
EC
System ChartEBS00M0B
*1: This sensor is not used to control the engine system under normal conditions.
*2: These signals are sent to the ECM through CAN communication line.
Multiport Fuel Injection (MFI) SystemEBS00M0C
INPUT/OUTPUT SIGNAL CHART
*1: Under normal conditions, this sensor is not for engine control operation.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
Input (Sensor) ECM Function Output (Actuator)
●Camshaft position sensor (PHASE)
●Crankshaft position sensor (POS)
●Mass air flow sensor
●Engine coolant temperature sensor
●Heated oxygen sensor 1
●Throttle position sensor
●Accelerator pedal position sensor
●Park/neutral position (PNP) switch
●Intake air temperature sensor
●Power steering pressure sensor
●Ignition switch
●Battery voltage
●Knock sensor
●Refrigerant pressure sensor
●Heated oxygen sensor 2 *1
●TCM (Transmission control module) *2
●Wheel sensor
●Air conditioner switch
●Electrical loadFuel injection & mixture ratio control Fuel injectors
Electronic ignition system Power transistors
Fuel pump control Fuel pump relay
On board diagnostic system MI (On the instrument panel)
Heated oxygen sensor 1 heater control Heated oxygen sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
Power valve control VIAS control solenoid valve
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control Air conditioner relay
Cooling fan control Cooling fan relays
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS)
Engine speed
Piston position
Fuel injec-
tion & mix-
ture ratio
controlFuel injectors Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Ignition switch Start signal
Knock sensor Engine knocking condition
Battery Battery voltage
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2 *
1Density of oxygen in exhaust gas
Wheel sensor Vehicle speed
Air conditioner switch Air conditioner operation

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

EC-72
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning
ignition switch “ON” or “START”.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided (CONSULT-
II display)
Just as ignition switch is turned
ON or Start40°C (104°F)
More than approx. 4 minutes after
ignition ON or Start80°C (176°F)
Except as shown above40 - 80°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cool-
ing fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening
in order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the nor-
mal condition.
So, the acceleration will be poor.
P1121 Electric throttle control actu-
ator
(ECM detect the throttle
valve is stuck open.)While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops,
the engine stalls.
The engine can restart in “N” or “P” position, and engine speed will not exceed 1,000
rpm or more.
P1122 Electric throttle control func-
tionECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1124
P1126Throttle control relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1128 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1229 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2122
P2123
P2127
P2128
P2138Accelerator pedal position
sensorThe ECM controls the electric throttle control actuator in regulating the throttle opening
in order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the nor-
mal condition.
So, the acceleration will be poor. DTC No. Detected items Engine operating condition in fail-safe mode

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)]
C
D
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F
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MA
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-90
[QR25(WITH 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)

EC-94
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
CONSULT-II FunctionEBS00M11
FUNCTION
107 Y/RIntake valve timing
control solenoid valve[Engine is running]
●Warm-up condition
●Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Warm-up condition
●When revving engine up to 2,000 rpm quicklyApproximately 4V - BATTERY
VOLTAGE (11 - 14V)
109
111W
WPower supply for
ECM[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
11 2 W / RThrottle control motor
relay[Ignition switch “OFF”]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]0 - 1.0V
11 3 W / BThrottle control motor
relay power supply[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
11 4 RThrottle control motor
(Open)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is depressing0 - 14V
11 5 B / YThrottle control motor
ground[Engine is running]
●Idle speedApproximately 0V
11 6 GThrottle control motor
(Close)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is releasing0 - 14V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0532E
PBIB0533E
PBIB0534E
Diagnostic test mode Function
Work supportThis mode enables a technician to adjust some devices faster and more accurately by following the
indications on the CONSULT-II unit.
Self-diagnostic resultsSelf-diagnostic results such as 1st trip DTC, DTCs and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*1
Data monitor Input/Output data in the ECM can be read.
Data monitor (SPEC)Input/Output of the specification for Basic fuel schedule, AFM, A/F feedback control value and the
other data monitor items can be read.
Active testDiagnostic Test Mode in which CONSULT-II drives some actuators apart from the ECMs and also
shifts some parameters in a specified range.
DTC & SRT confirmation The status of system monitoring tests and the self-diagnosis status/result can be confirmed.

EC-96
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
X: 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-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-48
.
CONSULT-II INSPECTION PROCEDURE
1. Turn ignition switch OFF.
2. Connect “CONSULT-II” to data link connector, which is located
under LH dash panel near the fuse box cover.
3. Turn ignition switch ON.
4. Touch “START (NISSAN BASED VHCL)”.
5. Touch “ENGINE”.
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Injectors×× ×
Power transistor (Ignition timing)×× ×
Throttle control motor relay×××
EVAP canister purge volume con-
trol solenoid valve××××
Air conditioner relay××
Fuel pump relay××××
Cooling fan relay××××
Heated oxygen sensor 1 heater××××
Heated oxygen sensor 2 heater××××
Intake valve timing control solenoid
valve××××
Calculated load value×××
VIAS control solenoid valve×× × ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
PBIB0376E
MBIB0233E

EC-100
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
B/FUEL SCHDL
[msec]×
●“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
IGN TIMING
[BTDC]×
●Indicates the ignition timing computed
by ECM according to the input signals.●When the engine is stopped, a
certain value is indicated.
A/F ALPHA-B1 [%]×
●The mean value of the air-fuel ratio
feedback correction 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 con-
trol.
CAL/LD VALUE [%]
●“Calculated load value” indicates the
value of the current airflow divided by
peak airflow.
MASS AIRFLOW
[g·m/s]
●Indicates the mass airflow computed by
ECM according to the signal voltage of
the mass air flow sensor.
PURG VOL C/V
[%]
●Indicates the EVAP canister purge vol-
ume control solenoid valve control value
computed by the ECM according to the
input signals.
●The opening becomes larger as the
value increases.
INT/V TIM (B1)
[°CA]
●Indicates [°CA] of intake camshaft
advanced angle.
INT/V SOL (B1) [%]
●The control condition of the intake valve
timing control solenoid valve (deter-
mined by ECM according to the input
signals) is indicated.
ON ... intake valve timing control is oper-
ating.
OFF ... Intake valve timing control is not
operating.
VIAS S/V
[ON/OFF]
●The control condition of the VIAS control
solenoid valve (determined by ECM
according to the input signals) is indi-
cated.
ON ... VIAS control solenoid valve is
operating.
OFF ... VIAS control solenoid valve is
not operating.
AIR COND RLY
[ON/OFF]×
●The air conditioner relay control condi-
tion (determined by ECM according to
the input signals) is indicated.
FUEL PUMP RLY
[ON/OFF]×
●Indicates the fuel pump relay control
condition determined by ECM according
to the input signals.
THRTL RELAY
[ON/OFF]
●Indicates the throttle control motor relay
control condition determined by the
ECM according to the input signals. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks

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