Page 1121 of 3189
![NISSAN ALMERA N16 2003 Electronic Repair Manual TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA (DC Voltage and Pulse
Signal)
204 L Air conditioner relay[Engine is running]
Air conditioner switch is “OFF”BATTERY VOLTAGE
(11 - 14V)
[Engine is running NISSAN ALMERA N16 2003 Electronic Repair Manual TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA (DC Voltage and Pulse
Signal)
204 L Air conditioner relay[Engine is running]
Air conditioner switch is “OFF”BATTERY VOLTAGE
(11 - 14V)
[Engine is running](/manual-img/5/57350/w960_57350-1120.png)
TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA (DC Voltage and Pulse
Signal)
204 L Air conditioner relay[Engine is running]
Air conditioner switch is “OFF”BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Both air conditioner switch and blower fan
switch are “ON”
(Compressor is operating)Approximately 0.1V
214 W/B Glow relay Refer to “Glow Control System”, EC-188.
218 B Sensors’ ground[Engine is running]
Warm-up condition
Idle speedApproximately 0V
219 LG/R Cooling fan relay (Low)[Engine is running]
Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Cooling fan is operatingApproximately 0.1V
221 LG/B Cooling fan relay (High)[Engine is running]
Cooling fan is not operating
Cooling fan is operating at low speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Cooling fan is operating at high speedApproximately 0.1V
223 WMass air flow sensor
power supply[Ignition switch “ON”]Approximately 5V
224 R Mass air flow sensor[Engine is running]
Warm-up condition
Idle speed1.5 - 2.0V
313 L/WElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 0.1V
314 L/RElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 0.4V
316 PUElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 2.5V
317 PElectronic control fuel
injection pump[Engine is running]
Warm-up condition
Idle speedApproximately 2.5V
325 G ECM relay (Self-shutoff)[Ignition switch “ON”]
[Ignition switch “OFF”]
For a few seconds after turning ignition switch
“OFF”Approximately 0.25V
[Ignition switch “OFF”]
A few seconds passed after turning ignition
switch “OFF”BATTERY VOLTAGE
(11 - 14V)
331 ORCrankshaft position sen-
sor (TDC) ground[Engine is running]
Warm-up condition
Idle speedApproximately 0V
334 B/REngine coolant tempera-
ture sensor ground[Ignition switch “ON”]Approximately 0V
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TROUBLE DIAGNOSIS — GENERAL DESCRIPTIONYD
ECM Terminals and Reference Value (Cont’d)
EC-67
Page 1125 of 3189

DescriptionNJEC0637Intermittent incidents (I/I) may occur. In many cases, the incident 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 malfunctioning area.
COMMON I/I REPORT SITUATIONSNJEC0637S01
STEP in Work Flow Situation
II The CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than “0”.
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 malfunctioningarea.
Diagnostic ProcedureNJEC0638
1 INSPECTION START
Erase DTCs. Refer to “HOW TO ERASE DTC”, EC-34.
GO TO 2.
2 CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection.
Refer to GI-23, “GROUND INSPECTION”.
OK or NG
OK GO TO 3.
NG Repair or replace.
3 SEARCH FOR ELECTRICAL INCIDENT
Perform GI-23, “Incident Simulation Tests”.
OK or NG
OKINSPECTION END
NG Repair or replace.
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TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTYD
Description
EC-71
Page 1132 of 3189

SEF987W
Component DescriptionNJEC0642The 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 film that is supplied with
electric current from the ECM. The temperature of the hot film is
controlled by the ECM a certain amount. The heat generated by the
hot film 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 film as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0643Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
MAS AIR/FL SEEngine: After warming up
Air conditioner switch: “OFF”
Shift lever: Neutral position
No-loadIdle 1.5 - 2.0V
ECM Terminals and Reference ValueNJEC0644Specification 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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
218 B Sensor’s ground[Engine is running]
Warm-up condition
Idle speedApproximately 0V
223 WMass air flow sensor
power supply[Ignition switch “ON”]Approximately 5V
224 R Mass air flow sensor[Engine is running]
Warm-up condition
Idle speed1.5 - 2.0V
On Board Diagnosis LogicNJEC0645This self-diagnosis has the one trip detection logic.
DTC Malfunction is detected when ... Check Items (Possible Cause)
P0100
0102An excessively high or low voltage from the sen-
sor is sent to ECM.Harness or connectors
(The sensor circuit is open or shorted.)
Mass air flow sensor
DTC P0100 MASS AIR FLOW SENYD
Component Description
EC-78
Page 1133 of 3189
SEF817Y
DTC Confirmation ProcedureNJEC0646WITH CONSULT-IINJEC0646S011) Turn ignition switch “ON”, and wait at least 6 seconds.
2) Select “DATA MONITOR” mode with CONSULT-II.
3) Start engine and wait at least 3 seconds.
4) If DTC is detected, go to “Diagnostic Procedure”, EC-81.
WITHOUT CONSULT-IINJEC0646S021) Turn ignition switch “ON”, and wait at least 6 seconds.
2) Start engine and wait at least 3 seconds.
3) Turn ignition switch “OFF”, wait at least 5 seconds and then
turn “ON”.
4) Perform “Diagnostic Test Mode II (Self-diagnostic results)” with
ECM.
5) If DTC is detected, go to “Diagnostic Procedure”, EC-81.
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DTC P0100 MASS AIR FLOW SENYD
DTC Confirmation Procedure
EC-79
Page 1134 of 3189
Wiring DiagramNJEC0647
YEC322A
DTC P0100 MASS AIR FLOW SENYD
Wiring Diagram
EC-80
Page 1135 of 3189
Diagnostic ProcedureNJEC0648
1 CHECK MAFS POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect mass air flow sensor harness connector.
SEF884Y
3. Turn ignition switch “ON”.
4. Check voltage between mass air flow sensor terminals 2, 4 and ground withCONSULT-II or tester.
SEF297X
OK or NG
OK GO TO 3.
NG GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E75, F36
Harness for open or short between mass air flow sensor and ECM
Harness for open or short between mass air flow sensor and ECM relay
Repair open circuit or short to ground or short to power in harness or connector.
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DTC P0100 MASS AIR FLOW SENYD
Diagnostic Procedure
EC-81
Page 1136 of 3189

3 CHECK MAFS GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
SEF380Y
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
OK GO TO 5.
NG GO TO 4.
4 DETECT MALFUNCTIONING PART
Check harness for open or short between mass air flow sensor and ECM.
Repair 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 1 and ECMterminal 224. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK GO TO 6.
NG Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0100 MASS AIR FLOW SENYD
Diagnostic Procedure (Cont’d)
EC-82
Page 1137 of 3189
6 CHECK MASS AIR FLOW SENSOR
1. Reconnect harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 224 (Mass air flow sensor signal) andground.
SEF441Z
4. If the voltage is out of specification, disconnect MAFS harness connector and connect it again.
Then repeat above check.
OK or NG
OK GO TO 7.
NG Replace mass air flow sensor.
7 CHECK INTERMITTENT INCIDENT
Refer to “TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT”, EC-71.
INSPECTION END
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DTC P0100 MASS AIR FLOW SENYD
Diagnostic Procedure (Cont’d)
EC-83