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![NISSAN X-TRAIL 2003 Service Repair Manual PRECAUTIONS
EC-487
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Do not disassemble ECM.
If battery cable is disconnected, the memory will return to
the initial ECM values.
The ECM will now st NISSAN X-TRAIL 2003 Service Repair Manual PRECAUTIONS
EC-487
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Do not disassemble ECM.
If battery cable is disconnected, the memory will return to
the initial ECM values.
The ECM will now st](/manual-img/5/57404/w960_57404-864.png)
PRECAUTIONS
EC-487
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Do not disassemble ECM.
If battery cable is disconnected, the memory will return to
the initial ECM values.
The ECM will now start to self-control at its initial values.
Engine operation can vary slightly when the cable is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.
When connecting ECM harness connector, fasten it
securely with levers as far as they will go as shown in the
figure.
When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.
Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.
Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.
Keep engine control system parts and harness dry.
Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to EC-543
.
Handle mass air flow sensor carefully to avoid damage.
Do not disassemble mass air flow sensor.
Do not clean mass air flow sensor with any type of deter-
gent.
Do not disassemble electric throttle control actuator.
Even a slight leak in the air intake system can cause seri-
ous incidents.
Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
PBIB1164E
PBIB1512E
PBIB0090E
MEF040D
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EC-488
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PRECAUTIONS
After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.
When measuring ECM signal with a circuit tester, connect
break-out box (SST) and Y-cable adapter (SST) between the
ECM and ECM harness connector.
When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
Do not operate fuel pump when there is no fuel in lines.
Tighten fuel hose clamps to the specified torque.
SAT652J
SEF348N
PBIB0513E
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![NISSAN X-TRAIL 2003 Service Repair Manual PRECAUTIONS
EC-489
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Do not depress accelerator pedal when starting.
Immediately after starting, do not rev up engine unneces-
sarily.
Do not rev u NISSAN X-TRAIL 2003 Service Repair Manual PRECAUTIONS
EC-489
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Do not depress accelerator pedal when starting.
Immediately after starting, do not rev up engine unneces-
sarily.
Do not rev u](/manual-img/5/57404/w960_57404-866.png)
PRECAUTIONS
EC-489
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Do not depress accelerator pedal when starting.
Immediately after starting, do not rev up engine unneces-
sarily.
Do not rev up engine just prior to shutdown.
When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.
–Keep the antenna as far as possible from the electronic
control units.
–Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
–Adjust the antenna and feeder line so that the standing-
wave radio can be kept smaller.
–Be sure to ground the radio to vehicle body.
Wiring Diagrams and Trouble DiagnosisEBS010WJ
When you read wiring diagrams, refer to the following:
GI-14, "How to Read Wiring Diagrams"
PG-2, "POWER SUPPLY ROUTING" for power distribution circuit
When you perform trouble diagnosis, refer to the following:
GI-10, "HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES"
GI-23, "How to Perform Efficient Diagnosis for an Electrical Incident"
SEF709Y
SEF708Y
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EC-490
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PREPARATION
PREPARATIONPFP:00002
Special Service ToolsEBS010WK
Tool number
Tool nameDescription
KV10117100
Heated oxygen
sensor wrenchLoosening or tightening heated oxygen sensor
with 22 mm (0.87 in) hexagon nut
KV10114400
Heated oxygen
sensor wrenchLoosening or tightening heated oxygen sensor
a: 22 mm (0.87 in)
EG17650301
Radiator cap tester
adapterAdapting radiator cap tester to radiator cap and
radiator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV109E0010
Break-out boxMeasuring ECM signals with a circuit tester
KV109E0080
Y-cable adapterMeasuring ECM signals with a circuit tester
S-NT379
S-NT636
S-NT564
NT825
NT826
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PREPARATION
EC-491
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Commercial Service ToolsEBS010WL
Tool name Description Description
Quick connector
releaseRemoving fuel tube quick connectors in engine
room
(Available in SEC. 164 of PARTS CATALOG: Part
No. 16441 6N210)
Fuel filler cap adapter Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
Oxygen sensor thread
cleaner
ie: (J-43897-18)
(J-43897-12)Reconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL
specification MIL-A-
907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
PBIC0198E
S-NT653
S-NT705
AEM488
S-NT779
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EC-492
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ENGINE CONTROL SYSTEM
ENGINE CONTROL SYSTEMPFP:23710
System DiagramEBS010WM
QR20DE ENGINE MODELS
PBIB2455E
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ENGINE CONTROL SYSTEM
EC-493
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QR25DE ENGINE MODELS
PBIB2456E
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EC-494
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ENGINE CONTROL SYSTEM
Vacuum Hose DrawingEBS010WN
QR20DE ENGINE MODELS
Refer to EC-494, "QR20DE ENGINE MODELS" for Vacuum Control System.
PBIB0489E