NISSAN LATIO 2008 Service Repair Manual

POWER SUPPLY AND GROUND CIRCUIT
EC-137
< SERVICE INFORMATION >
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POWER SUPPLY AND GROUND CIRCUIT
Wiring DiagramINFOID:0000000001702605
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
BBWA2625E

EC-138
< SERVICE INFORMATION >
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis Procedure
INFOID:0000000001702606
1.INSPECTION START
Start engine.
Is engine running?
Ye s o r N o
Ye s > > G O T O 8 .
No >> GO TO 2.
2.CHECK ECM POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF and then ON.
2. Check voltage between ECM terminal 93 and ground with CON-
SULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M69, E7
• 10A fuse
• Harness for open or short between ECM and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
Refer to EC-142, "
Ground Inspection".
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
10
11B
BECM ground[Engine is running]
• Idle speedBody ground
32 PECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition switch
OFF0 - 1.0V
[Ignition switch: OFF]
• More than a few seconds after turning ignition
switch OFFBATTERY VOLTAGE
(11 - 14V)
93 O Ignition switch[Ignition switch: OFF]0V
[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
105 GPower supply for
ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
108 B ECM ground[Engine is running]
• Idle speedBody ground
Voltage: Battery voltage
PBIA9561J

POWER SUPPLY AND GROUND CIRCUIT
EC-139
< SERVICE INFORMATION >
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OK or NG
OK >> GO TO 5.
NG >> Repair or replace ground connections.
5.CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 10, 11, 108 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F8, E8
• Harness for open or short between ECM and ground
>> Repair open circuit or short to power in harness or connectors.
7.CHECK ECM POWER SUPPLY CIRCUIT-II
1. Reconnect ECM harness connector.
2. Turn ignition switch ON.
3. Check voltage between IPDM E/R terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> Go to EC-531.
NG >> GO TO 8.
8.CHECK ECM POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON and then OFF.
:Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15
BBIA0698E
Continuity should exist.
Voltage: Battery voltage
PBIB2658E

EC-140
< SERVICE INFORMATION >
POWER SUPPLY AND GROUND CIRCUIT
3. Check voltage between ECM terminal 105 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 14.
NG (Battery voltage does not exist.)>>GO TO 9.
NG (Battery voltage exists for more than a few seconds.)>>GO TO
11 .
9.CHECK ECM POWER SUPPLY CIRCUIT-IV
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Check voltage between ECM terminal 32 and ground with CON-
SULT-II or tester.
OK or NG
OK >> GO TO 10.
NG >> GO TO 11.
10.CHECK ECM POWER SUPPLY CIRCUIT-V
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E43.
3. Check harness continuity between ECM terminal 105 and IPDM E/R terminal 4.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 17.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
11 .CHECK ECM POWER SUPPLY CIRCUIT-VI
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E43.
3. Check harness continuity between ECM terminal 32 and IPDM E/R terminal 7.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> GO TO 12.
12.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E8, F8
• Harness for open or short between ECM and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors. Voltage: After turning ignition switch OFF, battery
voltage will exist for a few seconds, then drop
approximately 0V.
PBIB3037E
Voltage: Battery voltage
PBIA9562J
Continuity should exist.
Continuity should exist.

POWER SUPPLY AND GROUND CIRCUIT
EC-141
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13.CHECK 20A FUSE
1. Disconnect 20A fuse from IPDM E/R.
2. Check 20A fuse.
OK or NG
OK >> GO TO 17.
NG >> Replace 20A fuse.
14.CHECK GROUND CONNECTIONS
1. Loosen and retighten ground screw on the body.
Refer to EC-142, "
Ground Inspection".
OK or NG
OK >> GO TO 15.
NG >> Repair or replace ground connections.
15.CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 10, 11, 108 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 17.
NG >> GO TO 16.
16.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F8, E8
• Harness for open or short between ECM and ground
>> Repair open circuit or short to power in harness or connectors.
17.CHECK INTERMITTENT INCIDENT
Refer to EC-136
.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-25, "IPDM E/R Power/Ground Circuit Inspection".
NG >> Repair open circuit or short to power in harness or connectors.
:Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15
BBIA0698E
Continuity should exist.

EC-142
< SERVICE INFORMATION >
POWER SUPPLY AND GROUND CIRCUIT
Ground Inspection
INFOID:0000000001702607
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 eye-
let make sure no ground wires have excess wire insulation.
For detailed ground distribution information, refer to PG-28, "
Ground Distribution".
PBIB1870E

DTC U1000, U1001 CAN COMMUNICATION LINE
EC-143
< SERVICE INFORMATION >
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DTC U1000, U1001 CAN COMMUNICATION LINE
DescriptionINFOID:0000000001702608
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 LogicINFOID:0000000001702609
*1: This self-diagnosis has the one trip detection logic (A/T, CVT).
The MIL will not light up for this self-diagnosis (M/T).
*2: The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001702610
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-144, "
Diagnosis Procedure".
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
U1000*
1
1000*1CAN communication
lineWhen ECM is not transmitting or receiving CAN
communication signal of OBD (emission related
diagnosis) for 2 seconds or more.• Harness or connectors
(CAN communication line is open or
shorted.)
U1001*
2
1001*2
When ECM is not transmitting or receiving CAN
communication signal other than OBD (emission-
related diagnosis) for 2 seconds or more.

EC-144
< SERVICE INFORMATION >
DTC U1000, U1001 CAN COMMUNICATION LINE
Wiring Diagram
INFOID:0000000001702611
Diagnosis ProcedureINFOID:0000000001702612
Go to LAN-23, "CAN System Specification Chart".
BBWA2626E

DTC U1010 CAN COMMUNICATION
EC-145
< SERVICE INFORMATION >
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DTC U1010 CAN COMMUNICATION
DescriptionINFOID:0000000001702613
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 LogicINFOID:0000000001702614
This self-diagnosis has the one trip detection logic (A/T, CVT).
The MIL will not light up for this self-diagnosis (M/T).
DTC Confirmation ProcedureINFOID:0000000001702615
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-145, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnosis ProcedureINFOID:0000000001702616
1.INSPECTION START
With CONSULT-II
1. Turn ignition switch ON.
2. Select “SELF-DIAG RESULTS” mode with CONSULT-II.
3. Touch “ERASE”.
4.Perform DTC Confirmation Procedure.
See EC-145, "
DTC Confirmation Procedure".
5. Is the 1st trip DTC U1010 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3.Perform DTC Confirmation Procedure.
See EC-145, "
DTC Confirmation Procedure".
4. Is the 1st trip DTC U1010 displayed again?
Ye s o r N o
Yes >> GO TO 2.
No >>INSPECTION END
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
U1010
1010CAN communication busWhen detecting error during the initial diagno-
sis for CAN controller of each control unit.•ECM
SEF058Y

EC-146
< SERVICE INFORMATION >
DTC U1010 CAN COMMUNICATION
2.REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to BL-211, "
ECM Re-communicating Function".
3. Perform EC-75, "
VIN Registration".
4. Perform EC-76, "
Accelerator Pedal Released Position Learning".
5. Perform EC-76, "
Throttle Valve Closed Position Learning".
6. Perform EC-76, "
Idle Air Volume Learning".
>>INSPECTION END