2002 NISSAN TERRANO air flow

TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA (DC Voltage and Pulse
Signal)
35 R Mass air flow sensorEngine is running.
Warm-up condition
Idle speed1.6 - 2.0V
37 LG/R A/T signal No. 2Engine is running.
Warm-up condition
Idle speedVoltage goes high up once in
a few seconds
SEF448Z
38 B/W Ignition switchIgnition switch ªOFFº
0V
Ignition switch ªONº
BATTERY VOLTAGE
(11 - 14V)
39
43B
BECM groundEngine is running.
Idle speedApproximately 0V
40 RElectronic control fuel
injection pumpEngine is running.
Warm-up condition
Idle speedApproximately 2.5V
42 OR
Data link connectorEngine is running.
Idle speed (CONSULT-II is connected and
turned on)Approximately 0V
64 OR/BApproximately 0V
65 OR/WLess than 9V
44 L/GCrankshaft position sen-
sor (TDC)Engine is running.
Warm-up condition
Idle speedApproximately 0V
SEF333Y
Engine is running.
Warm-up condition
Engine speed is 2,000 rpmApproximately 0V
SEF334Y
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
ECM Terminals and Reference Value (Cont'd)
EC-74

Description
Intermittent incidents (I/I) may occur. In many cases, the problem resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the custom-
er's complaint often do not recur on DTC visits. Realize also that the most frequent cause of I/I occurrences
is poor electrical connections. Because of this, the conditions under which the incident occurred may not be
clear. Therefore, circuit checks made as part of the standard diagnostic procedure may not indicate the spe-
cific problem area.
COMMON I/I REPORT SITUATIONS
STEP in Work Flow Situation
II The CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than ª0º.
III The symptom described by the customer does not recur.
IV DTC does not appear during the DTC Confirmation Procedure.
VI The Diagnostic Procedure for XXXX does not indicate the problem area.
Diagnostic Procedure
1 INSPECTION START
Erase DTCs. Refer to ªHOW TO ERASE DTCº, EC-33.
EGO TO 2.
2 CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection.
Refer to GI section (ªGROUND INSPECTIONº, ªCircuit Inspectionº).
OK or NG
OKEGO TO 3.
NGERepair or replace.
3 SEARCH FOR ELECTRICAL INCIDENT
Perform GI section, ªIncident Simulation Testsº.
OK or NG
OKEINSPECTION END
NGERepair or replace.
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTZD30DDTi
EC-78

Component Description
The mass air flow sensor (MAFS) is placed in the stream of intake
air. It measures the intake air flow rate by measuring a part of the
entire intake air flow. It consists of a hot wire that is supplied with
electric current from the ECM. The temperature of the hot wire is
controlled by the ECM a certain amount. The heat generated by the
hot wire is reduced as the intake air flows around it. The more air,
the greater the heat loss.
Therefore, the ECM must supply more electric current to maintain
the temperature of the hot wire as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
MAS AIR/FL SEIEngine: After warming up
IAir conditioner switch: ªOFFº
IShift lever: Neutral position
INo-loadIdle 1.6 - 2.0V
ECM Terminals and Reference Value
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)
35 R Mass air flow sensorEngine is running.
Warm-up condition
Idle speed1.6 - 2.0V
49 W Sensor's power supply Ignition switch ªONº
Approximately 5V
50 B Sensor's groundEngine is running.
Warm-up condition
Idle speedApproximately 0V
On Board Diagnosis Logic
Malfunction is detected when ... Check Items (Possible Cause)
IAn excessively high or low voltage from the sensor is sent to
ECM.IHarness or connectors
(The sensor circuit is open or shorted.)
IMass air flow sensor
SEF987W
DTC 0102 MASS AIR FLOW SENZD30DDTi
EC-88

DTC Confirmation Procedure
WITH CONSULT-II
1) Turn ignition switch ªONº, and wait at least 6 seconds.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait at least 3 seconds.
4) If DTC is detected, go to ªDiagnostic Procedureº, EC-92.
WITHOUT CONSULT-II
1) Turn ignition switch ªONº, and wait at least 6 seconds.
2) Start engine and wait at least 3 seconds.
3) Turn ignition switch ªOFFº, wait at least 5 seconds and then turn
ªONº.
4) Perform ªDiagnostic Test Mode II (Self-diagnostic results)º with
ECM.
5) If DTC is detected, go to ªDiagnostic Procedureº, EC-92.
SEF817Y
DTC 0102 MASS AIR FLOW SENZD30DDTi
EC-89

Wiring Diagram
LHD MODELS
YEC173A
DTC 0102 MASS AIR FLOW SENZD30DDTi
EC-90

RHD MODELS
YEC174A
DTC 0102 MASS AIR FLOW SENZD30DDTi
Wiring Diagram (Cont'd)
EC-91

Diagnostic Procedure
1 CHECK MAFS POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect mass air flow sensor harness connector.
MEC993D
3. Turn ignition switch ªONº.
4. Check voltage between mass air flow sensor terminals 2, 4 and ground with CONSULT-II or tester.
MEC973D
MTBL1318
OK or NG
OKEGO TO 3.
NGEGO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors M787, F66 (LHD models)
IHarness connectors F135, M842 (RHD models)
IHarness for open or short between mass air flow sensor and ECM
IHarness for open or short between mass air flow sensor and ECM relay
ERepair open circuit or short to ground or short to power in harness or connector.
DTC 0102 MASS AIR FLOW SENZD30DDTi
EC-92

3 CHECK MAFS GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
MEC994D
3. Check harness continuity between mass air flow sensor terminal 3 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 5.
NGEGO TO 4.
4 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F135, M842 (RHD models)
IHarness for open or short between mass air flow sensor and ECM
ERepair open circuit or short to ground or short to power in harness or connectors.
5 CHECK MAFS INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between mass air flow sensor terminal 5 and ECM terminal 35. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OKEGO TO 7.
NGEGO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F135, M842 (RHD models)
IHarness for open or short between mass air flow sensor and ECM
ERepair open circuit or short to ground or short to power in harness or connectors.
DTC 0102 MASS AIR FLOW SENZD30DDTi
Diagnostic Procedure (Cont'd)
EC-93