NISSAN PICK-UP 2001 Repair Manual

4 CHECK POWER SUPPLY
1. Disconnect mass air flow sensor harness connector.
AEC131A
2. Turn ignition switch ON.
3. Check voltage between terminal 3 and ground with CONSULT-II or tester.
AEC691
Voltage: Battery voltage
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E101, M5
+Harness for open or short between ECM relay and mass air flow sensor
+Harness for open or short between mass air flow sensor and ECM
©Repair harness or connectors.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3156

6 CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between mass air flow sensor terminal 2 and ECM terminal 55. Refer to EC-3154.
SEF124V
Continuity should exist.
4. Also check harness for short to ground or short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK INPUT SIGNAL CIRCUIT
1. Check harness continuity between terminal 1 and ECM terminal 54. Refer to wiring diagram.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3157

8 CHECK MASS AIR FLOW SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Start engine and warm it up to normal operating temperature.
4. Check voltage between ECM terminal 54 (mass air flow sensor signal) and ground.
SEF326V
MTBL0326
5. If the voltage is out of specification, disconnect mass air flow sensor harness connector and connect it again. Repeat
above check.
6. If NG, remove mass air flow sensor from air duct. Check hot wire for damage or dust.
SEF893J
OK or NG
OK©GO TO 9.
NG©Replace mass air flow sensor.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3158

9 CHECK SHIELD CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect joint connector-3.
3. Check the following.
+Continuity between joint connector-3 terminal 2 and ground
+Joint connector-3
(Refer to ªHARNESS LAYOUTº, in EL section.)
Continuity should exist.
4. Also check harness for short to power.
OK or NG
OK©GO TO 10.
NG©Repair open circuit or short to power in harness or connectors.
10 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-3123.
©INSPECTION END
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3159

SEF329V
Component DescriptionNEEC0066The intake air temperature sensor is mounted to the air duct hous-
ing. The sensor detects intake air temperature and transmits a sig-
nal to the ECM.
The temperature sensing unit uses a thermistor which is sensitive
to the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.
SEF012P

Intake air temperature
ÉC (ÉF)Voltage*
VResistance
kW
20 (68) 3.5 2.1 - 2.9
80 (176) 1.23 0.27 - 0.38
*: These data are reference values and are measured between ECM terminal 61
(Intake air temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
ECM Terminals and Reference ValueNEEC1556
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
43 B Sensors' ground[Engine is running]
+Idle speedApproximately 0V
61 P/BIntake air temperature sen-
sor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
intake air temperature.
On Board Diagnosis LogicNEEC0067
DTC
No.Trouble diagno-
sis nameDTC detecting condition Possible cause
P0112
0112Intake air tem-
perature sensor
circuit low inputAn excessively low voltage from the sensor is
sent to ECM.+Harness or connectors
(The sensor circuit is open or shorted.)
+Intake air temperature sensor
P0113
0113Intake air tem-
perature sensor
circuit high inputAn excessively high voltage from the sensor is
sent to ECM.
DTC P0112, P0113 IAT SENSORKA24DE (EURO OBD)
Component Description
EC-3160

FAIL-SAFE MODENEEC0067S01When the malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
Engine operating condition in fail-safe mode
The ECM functions on the assumption that the intake air temperature is 25ÉC (77ÉF).
DTC Confirmation ProcedureNEEC0068NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch OFF and wait at least 5 seconds before
conducting the next test.
SEF058Y
With CONSULT-II
1) Turn ignition switch ON.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3163.
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0112, P0113 IAT SENSORKA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3161

Wiring DiagramNEEC0069
GEC238A
DTC P0112, P0113 IAT SENSORKA24DE (EURO OBD)
Wiring Diagram
EC-3162

Diagnostic ProcedureNEEC0070
1 CHECK POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect intake air temperature sensor harness connector.
SEF329V
3. Turn ignition switch ON.
4. Check voltage between terminal 2 and ground with CONSULT-II or tester.
SEC271D
Voltage: Approximately 5V
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E101, M5
+Harness for open or short between ECM and intake air temperature sensor
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check harness continuity between intake air temperature sensor terminal 1 and engine ground. Refer to the Wiring Dia-
gram.
Continuity should exist.
3. Also check harness for short to power.
OK or NG
OK©GO TO 5.
NG©GO TO 4.
DTC P0112, P0113 IAT SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3163

4 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E101, M5
+Harness for open or short between ECM and intake air temperature sensor
©Repair open circuit or short to power in harness or connectors.
5 CHECK INTAKE AIR TEMPERATURE SENSOR
Check resistance as shown in the figure.
SEC272D
MTBL1306
OK or NG
OK©GO TO 6.
NG©Replace intake air temperature sensor.
6 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-3123.
©INSPECTION END
DTC P0112, P0113 IAT SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3164

SEF594K
Component DescriptionNEEC0072The 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 coolant temperature input. The sensor uses a thermistor
which is sensitive to the change in temperature. The electrical
resistance of the thermistor decreases as temperature increases.
SEF012P

Engine coolant temperature
ÉC (ÉF)Voltage*
VResistance
kW
þ10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
*: These data are reference values and are measured between ECM terminal 59
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
CONSULT-II Reference Value in Data Monitor
Mode
NEEC0073
MONITOR ITEM CONDITION SPECIFICATION
COOLAN TEMP/S+Engine: After warming up More than 70ÉC (158ÉF)
ECM Terminals and Reference ValueNEEC1557
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
43 B Sensors' ground[Engine is running]
+Idle speedApproximately 0V
59 LG/REngine coolant tempera-
ture sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
engine coolant tempera-
ture.
DTC P0117, P0118 ECT SENSORKA24DE (EURO OBD)
Component Description
EC-3165