2002 NISSAN TERRANO Service Repair Manual

Main Power Supply and Ground Circuit
ECM TERMINALS AND REFERENCE VALUE
Remarks: 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 damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
4 G ECM relay (Self-shutoff)Ignition switch ªONº
Ignition switch ªOFFº
For a few seconds after turning ignition switch
ªOFFºApproximately 0.25V
Ignition switch ªOFFº
A few seconds passed after turning ignition
switch ªOFFºBATTERY VOLTAGE
(11 - 14V)
38 B/W Ignition switchIgnition switch ªOFFº
0V
Ignition switch ªONº
BATTERY VOLTAGE
(11 - 14V)
39
43B
BECM groundEngine is running.
Idle speedApproximately 0V
56
61
11 6B/W
B/W
B/WPower supply for ECM Ignition switch ªONº
BATTERY VOLTAGE
(11 - 14V)
102 G/W Current returnEngine is running.
Idle speedBATTERY VOLTAGE
(11 - 14V)
106
11 2
11 8B
B
BECM groundEngine is running.
Idle speedApproximately 0V
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
EC-79

WIRING DIAGRAM
YEC171A
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-80

YEC172A
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-81

DIAGNOSTIC PROCEDURE
1 INSPECTION START
Start engine.
Is engine running?
YesorNo
Ye sEGO TO 14.
NoEGO TO 2.
2 CHECK ECM POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ªONº.
2. Check voltage between ECM terminal 38 and ground with CONSULT-II or tester.
SEF397Y
OK or NG
OKEGO TO 4.
NGEGO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
I10A fuse
IHarness for open or short between ECM and fuse
ERepair open circuit or short to ground or short to power in harness or connectors.
4 CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 39, 43, 106, 112, 118 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 6.
NGEGO TO 5.
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-82

5 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F108, E225
IHarness connectors M842, F135 (RHD models)
IHarness for open or short between ECM and engine ground
ERepair open circuit or short to ground or short to power in harness or connectors.
6 CHECK ECM POWER SUPPLY CIRCUIT-II
1. Reconnect ECM harness connector.
2. Turn ignition switch ªONº and then ªOFFº.
3. Check voltage between ECM terminals 56, 61, 116 and ground with CONSULT-II or tester.
SEF288Z
OK or NG
OKECheck electronic control fuel injection pump power supply circuit. Refer to ªDiagnostic
Procedureº, EC-180.
NG (Battery voltage does not
exist.)EGO TO 7.
NG (Battery voltage exists for
more than a few seconds.)EGO TO 13.
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-83

7 CHECK ECM POWER SUPPLY CIRCUIT-III
1. Disconnect ECM relay.
MEC021E
2. Check voltage between relay terminals 2, 3 and ground with CONSULT-II or tester.
MEC978DVoltage: Battery Voltage
OK or NG
OKEGO TO 9.
NGEGO TO 8.
8 DETECT MALFUNCTIONING PART
Check the following.
I10A fuse
I15A fuse
IHarness for open or short between ECM relay and battery
ERepair open circuit or short to ground or short to power in harness or connectors.
9 CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 4 and ECM relay terminal 1. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 11.
NGEGO TO 10.
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-84

10 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors M787, F66 (LHD models)
IHarness for open or short between ECM and ECM relay
ERepair open circuit or short to ground or short to power in harness or connectors.
11 CHECK ECM POWER SUPPLY CIRCUIT-IV
1. Check harness continuity between ECM terminals 56, 61, 116 and ECM relay terminal 5. Refer to Wiring Diagram.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 13.
NGEGO TO 12.
12 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors M787, F66 (LHD models)
IHarness for open or short between ECM and ECM relay
ERepair open circuit or short to ground or short to power in harness or connectors.
13 CHECK ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between ECM relay terminals 3 and 5, 6 and 7.
SEF296X
OK or NG
OKEGO TO 14.
NGEReplace ECM relay.
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-85

14 CHECK ECM POWER SUPPLY CIRCUIT-V
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ªONº.
3. Check voltage between ECM terminal 102 and ground with CONSULT-II or tester.
SEF290Z
OK or NG
OKEGO TO 16.
NGEGO TO 15.
15 DETECT MALFUNCTIONING PART
Check the following.
I10A fuse
IHarness for open or short between ECM and fuse
ERepair open circuit or short to ground or short to power in harness or connectors.
16 CHECK ECM POWER SUPPLY CIRCUIT-VI
1. Turn ignition switch ªOFFº.
2. Disconnect ECM relay.
MEC021E
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminals 56, 61, 116 and ECM relay terminal 5. Refer to Wiring Diagram.
Continuity should exist.
5. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 18.
NGEGO TO 17.
TROUBLE DIAGNOSIS FOR POWER SUPPLYZD30DDTi
Main Power Supply and Ground Circuit
(Cont'd)
EC-86