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![NISSAN X-TRAIL 2003 Service Repair Manual POWER SUPPLY AND GROUND CIRCUIT
EC-127
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6. CHECK ECM POWER SUPPLY CIRCUIT-II
1. Disconnect ECM relay.
2. Check voltage between ECM relay terminals 1 and NISSAN X-TRAIL 2003 Service Repair Manual POWER SUPPLY AND GROUND CIRCUIT
EC-127
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6. CHECK ECM POWER SUPPLY CIRCUIT-II
1. Disconnect ECM relay.
2. Check voltage between ECM relay terminals 1 and](/manual-img/5/57404/w960_57404-504.png)
POWER SUPPLY AND GROUND CIRCUIT
EC-127
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6. CHECK ECM POWER SUPPLY CIRCUIT-II
1. Disconnect ECM relay.
2. Check voltage between ECM relay terminals 1 and 6 and
ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E61, F38
20A fuse
Harness for open or short between ECM relay and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 111 and ECM relay terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors F41, M61
Harness for open or short between ECM relay and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB1973E
Voltage: Battery voltage
SEF420X
Continuity should exist.
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EC-128
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POWER SUPPLY AND GROUND CIRCUIT
10. CHECK ECM RELAY
Refer to EC-131, "
Component Inspection" .
OK or NG
OK >> Go to EC-417, "IGNITION SIGNAL" .
NG >> Replace ECM relay.
11 . CHECK ECM POWER SUPPLY CIRCUIT-III
1. Stop engine and wait at least 10 seconds.
2. Turn ignition switch ON and then OFF.
3. Check voltage between ECM terminals 119, 120 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 17.
NG (Battery voltage does not exist.)>>GO TO 12.
NG (Battery voltage exists for more than a few seconds.)>>GO TO 14.
12. CHECK ECM POWER SUPPLY CIRCUIT-IV
1. Disconnect ECM relay.
2. Check voltage between ECM relay terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 14.
NG >> GO TO 13.Voltage: After turning ignition switch OFF, battery
voltage will exist for a few seconds, then
drop approximately 0V.
PBIB1630E
PBIB1973E
Voltage: Battery voltage
SEF860T
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POWER SUPPLY AND GROUND CIRCUIT
EC-129
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13. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E60, F36
10A fuse
Harness for open or short between ECM relay and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
14. CHECK ECM POWER SUPPLY CIRCUIT-V
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 119, 120 and ECM relay terminal 5.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 16.
NG >> GO TO 15.
15. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors F41, M61
Harness for open or short between ECM relay and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
16. CHECK ECM RELAY
Refer to EC-131, "
Component Inspection" .
OK or NG
OK >> GO TO 17.
NG >> Replace ECM relay.Continuity should exist.
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EC-130
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POWER SUPPLY AND GROUND CIRCUIT
17. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body.
Refer to EC-131, "
Ground Inspection" .
OK or NG
OK >> GO TO 18.
NG >> Repair or replace ground connections.
18. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 1, 115, 116 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 19.
NG >> Repair open circuit or short to power in harness or connectors.
19. CHECK INTERMITTENT INCIDENT
Refer to EC-123, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
PBIB2021E
Continuity should exist.
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![NISSAN X-TRAIL 2003 Service Repair Manual POWER SUPPLY AND GROUND CIRCUIT
EC-131
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Component InspectionEBS010MA
ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check NISSAN X-TRAIL 2003 Service Repair Manual POWER SUPPLY AND GROUND CIRCUIT
EC-131
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Component InspectionEBS010MA
ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check](/manual-img/5/57404/w960_57404-508.png)
POWER SUPPLY AND GROUND CIRCUIT
EC-131
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Component InspectionEBS010MA
ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between relay terminals 3 and 5, 6 and 7.
3. If NG, replace ECM relay.
Ground Inspection EBS011V6
Ground connections are very important to the proper operation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and other corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
Electronically controlled circuits are very sensitive to proper grounding. A loose or corroded ground can drasti-
cally affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit. Even
when the ground connection looks clean, there can be a thin film of rust on the surface.
When inspecting a ground connection follow these rules:
Remove the ground bolt or screw.
Inspect all mating surfaces for tarnish, dirt, rust, etc.
Clean as required to assure good contact.
Reinstall bolt or screw securely.
Inspect for “add-on” accessories which may be interfering with the ground circuit.
If several wires are crimped into one ground eyelet terminal, check for proper crimps. Make sure all of the
wires are clean, securely fastened and providing a good ground path. If multiple wires are cased in one
eyelet make sure no ground wires have excess wire insulation.
For detailed ground distribution information, refer to PG-13, "
Ground Distribution" .
Condition Continuity
12V direct current supply between
terminals 1 and 2Ye s
OFF No
PBIB0077E
PBIB1870E
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![NISSAN X-TRAIL 2003 Service Repair Manual EC-132
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DTC U1000, U1001 CAN COMMUNICATION LINE
DTC U1000, U1001 CAN COMMUNICATION LINEPFP:23710
DescriptionEBS010MB
CAN (Controller Area Network) is a serial communication line NISSAN X-TRAIL 2003 Service Repair Manual EC-132
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DTC U1000, U1001 CAN COMMUNICATION LINE
DTC U1000, U1001 CAN COMMUNICATION LINEPFP:23710
DescriptionEBS010MB
CAN (Controller Area Network) is a serial communication line](/manual-img/5/57404/w960_57404-509.png)
EC-132
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DTC U1000, U1001 CAN COMMUNICATION LINE
DTC U1000, U1001 CAN COMMUNICATION LINEPFP:23710
DescriptionEBS010MB
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagnosis LogicEBS010MC
*1: These self-diagnosis have the one trip detection logic.
*2: The MI will not light up for this self-diagnosis.
DTC Confirmation ProcedureEBS010MD
1. Turn ignition switch ON and wait at least 3 seconds.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-134, "
Diagnostic Procedure" .
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
U1000*
1
1000*1CAN communication
line
ECM cannot communicate to other control
units.
ECM cannot communicate for more than the
specified time.
Harness or connectors
(CAN communication line is open or
shorted.) U1001*
2
1001*2
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DTC U1000, U1001 CAN COMMUNICATION LINE
EC-133
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Wiring DiagramEBS010ME
TBWA0595E
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EC-134
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DTC U1000, U1001 CAN COMMUNICATION LINE
Diagnostic ProcedureEBS010MF
Go to LAN-4, "CAN Communication Unit" .