2001 NISSAN X-TRAIL check engine

POWER SUPPLY CIRCUIT FOR ECM
EC-1447
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13.CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminals A5, A6, A7 and engine ground. Refer to Wiring Dia-
gram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 14.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
14.CHECK INTERMITTENT INCIDENT
Refer to EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS003PG
ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between relay terminals 3 and 5, 6 and 7.
3. If NG, replace ECM relay.Continuity should exist.
Condition Continuity
12V direct current supply between ter-
minals 1 and 2Ye s
OFF No
PBIB0077E

EC-1452
[YD]
DTC P0100 MASS AIR FLOW SENSOR (MAFS)
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
On Board Diagnosis LogicEBS004Q3
DTC Confirmation ProcedureEBS004Q4
WITH CONSULT-II
1. 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 EC-1454, "
Diagnostic Procedure" .
D24
D26G
GECM relay (self-shutoff)[Ignition switch “ON”]
[Ignition switch “OFF”]●For a few seconds after turning ignition
switch "OFF"Approximately 0V
[Ignition switch “OFF”]
●A few seconds passed after turning ignition
switch "OFF"BATTERY VOLTAGE
(11 - 14V) TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse Signal)
DTC Malfunction is detected when ... Check Items (Possible Cause)
P0100
●An excessively high or low voltage from the sensor
is sent to ECM.●Harness or connectors
(The sensor circuit is open or shorted.)
●Mass air flow sensor
SEF817Y

EC-1454
[YD]
DTC P0100 MASS AIR FLOW SENSOR (MAFS)
Diagnostic Procedure
EBS004Q6
1. CHECK MAFS POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect mass air flow sensor harness connector.
3. Turn ignition switch “ON”.
4. Check voltage between mass air flow sensor terminals 2, 4 and
ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING PART
Check the following.
●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 connectors.
3. CHECK MAFS GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
3. Check harness continuity between mass air flow sensor terminal
3 and engine ground. Refer to Wiring Diagram.
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.
SEF884Y
Terminal Voltage
2 Approximately 5V
4 Battery voltage
PBIB0360E
Continuity should exist.
PBIB0385E

DTC P0100 MASS AIR FLOW SENSOR (MAFS)
EC-1455
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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 ECM terminal A10. Refer to Wiring
Diagram.
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.
6.CHECK MASS AIR FLOW SENSOR
Refer to EC-1455, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace mass air flow sensor.
7.CHECK INTERMITTENT INCIDENT
Refer to EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS004Q7
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 A10 (Mass air flow sensor
signal) and ground.
4. If the voltage is out of specification, disconnect MAFS harness
connector and connect it again.
Then repeat above check.
Removal and InstallationEBS008YD
MASS AIR FLOW SENSOR
Refer to EM-120, "AIR CLEANER AND AIR DUCT" . Continuity should exist.
Condition Voltage V
Ignition switch "ON" (Engine stopped.) Approx. 1.0
Idle (Engine is warmed up to normal
operating temperature.)1.0 - 2.5
2,000 rpm (Engine is warmed up to nor-
mal operating temperature.)2.1 - 2.7
PBIB0361E

EC-1456
[YD]
DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (CIRCUIT)
DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (CIRCUIT)
PFP:22630
DescriptionEBS004Q8
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 coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.

*: These data are reference values and measured between ECM terminal A11
(Engine coolant temperature sensor) 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.
On Board Diagnosis LogicEBS004Q9
DTC Confirmation ProcedureEBS004QA
WITH CONSULT-II
1. Turn ignition switch “ON”.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If DTC is detected, go to EC-1458, "
Diagnostic Procedure" .
SEF594K
Engine coolant tempera-
ture °C (°F)Voltage* (V) Resistance (kΩ)
−10 (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
SEF012P
DTC Malfunction is detected when ... Check Items (Possible Cause)
P0115
●An excessively high or low voltage from the sensor
is sent to ECM.●Harness or connectors
(The sensor circuit is open or shorted.)
●Engine coolant temperature sensor
SEF817Y

EC-1458
[YD]
DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (CIRCUIT)
Diagnostic Procedure
EBS004QC
1. CHECK ECTS POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”.
2. Disconnect engine coolant temperature sensor harness connec-
tor.
3. Turn ignition switch “ON”.
4. Check voltage between ECTS terminal 1 and ground with CON-
SULT-II or tester.
OK or NG
OK >> GO TO 2.
NG >> Repair harness or connectors.
2. CHECK ECTS GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between ECTS terminal 2 and engine ground. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connectors.
3. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-1459, "
Component Inspection" .
OK or NG
OK >> GO TO 4.
NG >> Replace engine coolant temperature sensor.
4. CHECK INTERMITTENT INCIDENT
Refer to EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
PBIB0374E
Voltage: Approximately 5V
PBIB0080E
Continuity should exist.

DTC P0115 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (CIRCUIT)
EC-1459
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Component InspectionEBS004QD
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.

*: These data are measured between ECM terminal A11 (Engine coolant tem-
perature sensor) and body ground.
2. If NG, replace engine coolant temperature sensor.
Removal and InstallationEBS008YF
ENGINE COOLANT TEMPERATURE SENSOR
Refer to EM-182, "CYLINDER HEAD" .
PBIB0081E
Engine coolant temperature °C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

DTC P0120 ACCELERATOR PEDAL POSITION SENSOR
EC-1461
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On Board Diagnosis LogicEBS004R8
DTC Confirmation ProcedureEBS004R9
WITH CONSULT-II
1. Turn ignition switch “ON”.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Depress and release fully accelerator pedal slowly.
4. If DTC is detected, go to EC-1463, "
Diagnostic Procedure" .
A26 LG/RAccelerator pedal position
sensor 2 ground[Ignition switch “ON”]Approximately 0V
A28 PU/RAccelerator pedal position
sensor 1 power supply [Ignition switch “ON”]Approximately 5V
B15 WAccelerator pedal position
sensor 1[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.8 - 1.3V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 3.5V
B16 GAccelerator pedal position
sensor 2[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully released0.3 - 1.8V
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully depressedMore than 3.0V
B23 GY/LAccelerator pedal position
sensor 2 power supply[Ignition switch “ON”]Approximately 5V
D14 G/YAccelerator pedal
released position switch[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal slightly depressedBATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]
●Engine stopped
●Accelerator pedal fully releasedApproximately 0V TERMI-
NAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse Signal)
DTC Malfunction is detected when ... Check Items (Possible Cause)
P0120
●An improper voltage signal from accelerator pedal
position sensor 1 and/or 2 is send to ECM.●Harness or connectors
(The sensor circuit is open or shorted.)
●Accelerator pedal position sensor 1
●Accelerator pedal position sensor 2
●Accelerator pedal released position switch
SEF817Y