2002 NISSAN TERRANO check engine

qA
CHECK POWER SUPPLY-III.
1. Turn ignition switch to ªONº position
and then to ªLOCKº position.
2. Check voltage between ECM connector
terminals
107,108,109and engine
ground with CONSULT-II or tester.
Voltage:
After turning ignition switch to
ªLOCKº position, battery voltage
will exist for a few seconds, then
drop to approximately 0V.
NG
EOK
Go toqBªCHECK
GROUND CIRCUITº.
Case-1: Battery voltage does
not exist.
Case-2: Battery voltage exists
for more than a few
seconds.
Case-1
Case-2
EGo toªCHECK ECM
RELAYº.
CHECK HARNESS CONTINUITY
BETWEEN ECM RELAY AND ECM.
1. Disconnect ECM harness connector.
2. Disconnect ECM relay harness connec-
tor.
3. Check harness continuity between
ECM connector terminals
325and
ECM relay connector terminalq
2, and
ECM connector terminals
107,108,
109and ECM relay connector termi-
nalq
5. Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following:
IHarness connectors
M787,F66(LHD mod-
els)
IHarness for open or
short-circuit between
ECM relay connector
and ECM connector.
If NG, repair harness or
connectors.
CHECK VOLTAGE BETWEEN ECCS
RELAY AND ENGINE GROUND.
Check voltage between ECM relay con-
nector terminalsq
1,q3and engine ground
with CONSULT-II or tester.
Voltage: Battery voltage
OK
ENG
Check the following:
I20A fuse
IFuse box and battery
connections
IHarness for open or
short-circuit between
ECM relay and battery
If NG, replace fuse or
repair harness or connec-
tors.
CHECK ECM RELAY.
1. Remove ECM relay.
2. Apply 12V direct current between relay
terminalsq
1andq2.
3. Check continuity between relay termi-
nalsq
3andq5.
12V (q
1-q2) applied:
Continuity exists.
No voltage applied:
No continuity
OK
ENG
Replace ECM relay.
qB
MEC944D
MEC945D
NEF350
H
H
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYTD27Ti
Diagnostic Procedure (Cont'd)
EC-354

qB
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Check harness continuity between
ECM connector terminals
104,105,
106and engine ground. Refer to wir-
ing diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following:
IEngine ground connec-
tions
IHarness for open or
short-circuit between
ECM and engine ground
If NG, repair harness or
connectors.
Check ECM pin terminals for damage and
check the connection of ECM harness
connector.
INSPECTION END
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYTD27Ti
Diagnostic Procedure (Cont'd)
EC-355

Component Description
MASS AIR FLOW SENSOR (MAFS)
The mass air flow sensor measures the intake air flow rate by
monitoring a part of the entire flow. Measurements are made by the
ECM which receives electrical signals from the mass air flow sen-
sor which is proportional to the amount of heat emitted from the hot
wire placed in the stream of the intake air.
When intake air flows into the intake manifold through a route
around the hot wire, the heat generated by the hot wire is carried
away by the air flow. The amount of heat detected depends on the
volume of air flow. The temperature of the hot wire is automatically
controlled to maintain it within a finite range regardless of the air
flow rate by regulating the current supplied to the hot wire.
The ECM monitors the air flow by means of the corresponding
electric change.
On Board Diagnosis Logic
DTC Malfunction is detected when...Check Items
(Possible Cause)
P0100
0102IAn excessively high or low voltage from the sensor is
entered to ECM.IHarness or connectors
(The sensor circuit is open or short-circuited.)
IMass air flow sensor
DTC Confirmation Procedure
WITH CONSULT-II
1) Turn ignition switch to ªONº position.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait for at least 15 seconds.
WITHOUT CONSULT-II
1) Start engine and wait for at least 15 seconds.
2) Turn ignition switch off, wait for at least 5 seconds and then turn
on.
3) Perform ªDiagnostic Test Mode IIº (Self-diagnostic results).
SEF781K
SEF817Y
DTC P0100 MASS AIR FLOW SENTD27Ti
EC-356

Diagnostic Procedure
INSPECTION START
CHECK POWER SUPPLY.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect mass air flow sensor har-
ness connector.
3. Turn ignition switch to ªONº position.
4. Check voltage between mass air flow
sensor connector terminalq
2and
engine ground with CONSULT-II or
tester.
Voltage: Battery positive voltage
OK
ENG
Check the following:
I20A fuse
IECM Relay
IHarness continuity
between ECM relay (coil
and load side) connector
and battery supply
IHarness connectors
F100,M755(RHD mod-
els)
IHarness connectors
M787,F66(LHD mod-
els)
IHarness continuity
between ECM relay con-
nector and Mass Air
Flow Sensor Connector.
If NG, replace 20A fuse or
ECM relay, or repair har-
ness or connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Loosen and retighten engine ground
screws.
4. Check harness continuity between
mass air flow sensor harness connec-
tor terminalq
3and ECM connector ter-
minal218. Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following.
IHarness connectors
F100,M755(RHD mod-
els)
IHarness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK INPUT SIGNAL CIRCUIT.
Check harness continuity between mass
air flow sensor connector terminalq
4and
ECM connector terminal223. Refer to
wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following.
IHarness connectors
F100,M755(RHD mod-
els)
IHarness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK INPUT SIGNAL CIRCUIT.
Check harness continuity between mass
air flow sensor connector terminalq
5and
ECM connector terminal224. Refer to
wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following.
IHarness connectors
F100,M755(RHD mod-
els)
IHarness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK COMPONENT
(Mass air flow sensor).
Refer to ªCOMPONENT INSPECTIONº,
EC-360.
OK
ENG
Replace mass air flow sen-
sor.
qA
NEF664
NEF591
NEF352
H
H
H
H
H
H
DTC P0100 MASS AIR FLOW SENTD27Ti
EC-359

qA
Disconnect and reconnect harness
connectors, then retest.
Trouble is not fixed.
Check ECM pin terminals for damage or
the connection of ECM harness connector.
Reconnect ECM harness connector and
retest.
INSPECTION END
Component Inspection
MASS AIR FLOW SENSOR
1. Turn ignition switch to ªONº position.
2. Start engine and warm it up sufficiently.
3. Check voltage between mass air flow sensor connector termi-
nalq
5and engine ground.
Condition Voltage V
Ignition switch ªONº position (Engine stopped.) Approx. 1.0
Idle (Engine is warmed-up sufficiently.) Approx. 2.2
4. If NG, remove mass air flow sensor from air duct. Check hot film
for damage or dust.
MEC957D
NEF669
H
H
H
DTC P0100 MASS AIR FLOW SENTD27Ti
Diagnostic Procedure (Cont'd)
EC-360

Component Description
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine cool-
ant temperature input. The sensor comprises a thermistor which is
sensitive to the change in temperature. The electrical resistance of
the thermistor decreases as temperature increases.

Engine coolant
temperature
ÉC (ÉF)Voltage
(V)Resistance
(kW)
þ10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.1 - 2.9
50 (122) 2.3 0.68 - 1.00
90 (194) 1.0 0.236 - 0.260
On Board Diagnosis Logic
DTC Malfunction is detected when ...Check Items
(Possible Cause)
P0115
0103IAn excessively high or low voltage from the sensor is
input to ECM.IHarness or connectors
(The sensor circuit is open or short-circuited.)
IEngine coolant temperature sensor
DTC Confirmation Procedure
WITH CONSULT-II
1) Turn ignition switch to ªONº position.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
WITHOUT CONSULT-II
1) Turn ignition switch to ªONº position and wait at least 5 sec-
onds.
2) Turn ignition switch to ªLOCKº position, wait at least 5 seconds
and then turn to ªONº position.
3) Perform diagnostic test mode II (Self-diagnostic results).
SEF594K
SEF012P
DTC P0115 COOLANT TEMP SENTD27Ti
EC-361

Diagnostic Procedure
INSPECTION START
CHECK POWER SUPPLY.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect engine coolant temperature
sensor harness connector.
3. Turn ignition switch to ªONº position.
4. Check voltage between engine coolant
temperature sensor connector terminal
q
1and engine ground with CONSULT-II
or tester.
Voltage:
Approximately 4.9V
OK
ENG
Check the following:
IHarness connectors
E151,F138(LHD model)
E151,M843(RHD
model)
IHarness for open or
short circuit between
ECM and engine coolant
temperature sensor.
If NG, repair harness or
connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Check harness continuity between
engine coolant temperature sensor
connector terminalq
2and ECM terminal
334. Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Check the following:
IHarness connectors
E151,F138(LHD model)
E151,M843(RHD
model)
IHarness for open or
short circuit between
ECM and engine coolant
temperature sensor.
If NG, repair harness or
connectors.
CHECK COMPONENT
(Engine coolant temperature sensor).
Refer to EC-364.
OK
ENG
Replace engine coolant
temperature sensor.
Disconnect and reconnect harness con-
nectors in the circuit. Then retest.
Trouble is not fixed.
Check ECM pin terminals for damage and
check the connection of ECM harness
connector. Reconnect ECM harness con-
nector and retest.
INSPECTION END
NEF487
NEF670
H
H
H
H
H
H
DTC P0115 COOLANT TEMP SENTD27Ti
EC-363

Component Inspection
ENGINE COOLANT TEMPERATURE SENSOR
Check resistance as shown in the figure.
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.0
90 (194) 0.236 - 0.260
If NG, replace engine coolant temperature sensor.SEF152P
SEF012P
DTC P0115 COOLANT TEMP SENTD27Ti
EC-364