2001 NISSAN PICK-UP Repair Manual

DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0102
0102An excessively low voltage from the sensor is sent to
ECM* when engine is running.+Harness or connectors
(The sensor circuit is open or shorted.)
+Intake air leaks
+Mass air flow sensor
*: When this malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
FAIL-SAFE MODENEEC1551S01
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuitEngine speed will not rise more than 2,400 rpm due to the fuel
cut.
DTC Confirmation ProcedureNEEC1552CAUTION:
Always drive vehicle at a safe speed.
NOTE:
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
PROCEDURE FOR DTC P0103NEEC1552S01With CONSULT-II
1) Turn ignition switch ON.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 6 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3155.
If 1st trip DTC is not detected, go to next step.
5) Start engine and let it idle for at least 6 seconds.
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3155.
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
On Board Diagnosis Logic
EC-3152

SEF058Y
PROCEDURE FOR DTC P0102NEEC1552S02With CONSULT-II
1) Turn ignition switch ON.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait 5 seconds at most.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-3155.
With GST
Follow the procedure ªWith CONSULT-IIº.
NOTE:
If 1st trip DTC is confirmed after more than 5 seconds, there may
be malfunction C.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
DTC Confirmation Procedure
EC-3153

Wiring DiagramNEEC1554
GEC237A
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Wiring Diagram
EC-3154

Diagnostic ProcedureNEEC1555
1 INSPECTION START
Which malfunction (P0102, P0103) is duplicated?
P0102 or P0103
P0103©GO TO 3.
P0102©GO TO 2.
2 CHECK INTAKE SYSTEM
Check the followings for connection.
+Air duct
+Air cleaner
+Vacuum hoses
+Intake air passage between air duct to collector
OK or NG
OK©GO TO 3.
NG©Reconnect the parts.
3 RETIGHTEN GROUND SCREWS
1. Turn ignition switch OFF.
2. Loosen and retighten engine ground screws.
SEC309D
©GO TO 4.
DTC P0102, P0103 MAF SENSORKA24DE (EURO OBD)
Diagnostic Procedure
EC-3155

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