2001 NISSAN ALMERA N16 Ignition

Diagnostic ProcedureNJEC0070
1 CHECK POWER SUPPLY (Models with intake air temperature sensor in mass air flow sensor)
1. Turn ignition switch ªOFFº.
2. Disconnect mass air flow sensor harness connector.
JEF105Y
3. Turn ignition switch ªONº.
4. Check voltage between terminal 5 and ground with CONSULT-II or tester.
SEC503C
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between ECM and intake air temperature sensor
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between intake air temperature sensor harness connector terminal 2 and engine ground.
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 5.
NG©GO TO 4.
4 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between ECM and intake air temperature sensor
©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0110 INTAKE AIR TEMPERATURE SENSORQG
Diagnostic Procedure
EC-161

Fail-safe ModeNJEC0566
Detected items Engine operating condition in fail-safe mode
Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning ignition switch
ªONº or ªSTARTº.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided (CONSULT-II
display)
Just as ignition switch is turned ON or Start 40ÉC (104ÉF)
More than approx. 4 minutes after ignition ON or
Start80ÉC (176ÉF)
Except as shown above40 - 80ÉC (104 - 176ÉF)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates
while the engine is running.
SEF013Y
DTC Confirmation ProcedureNJEC0075NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº.
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-166 .
With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0115 ENGINE COOLANT TEMPERATURE SENSOR (ECTS)
(CIRCUIT)
QG
Fail-safe Mode
EC-164

Diagnostic ProcedureNJEC0077
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect engine coolant temperature sensor harness connector.
SEF999W
3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and ground with CONSULT-II or tester.
SEF301X
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM and engine coolant temperature sensor.
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between engine coolant temperature sensor harness connector terminal 2 and engine
ground.
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 5.
NG©GO TO 4.
DTC P0115 ENGINE COOLANT TEMPERATURE SENSOR (ECTS)
(CIRCUIT)
QG
Diagnostic Procedure
EC-166

Component DescriptionNJEC0079NOTE:
If DTC P0120 (0120) is displayed with DTC P0510 (0510), first perform trouble diagnosis for DTC P0510,
EC-321.
The throttle position sensor responds to the accelerator pedal movement. This sensor is a kind of potentiom-
eter which transforms the throttle position into output voltage, and emits the voltage signal to the ECM. In
addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal
to the ECM.
Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sen-
sor. This sensor controls engine operation such as fuel cut. On the other hand, the ªWide open and closed
throttle position switchº, which is built into the throttle position sensor unit, is not used for engine control.
NEF308A
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0080Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
THRTL POS SEN+Engine: Idle Throttle valve: fully closed 0.15 - 0.85V
+Ignition switch: ON
(Engine stopped)Throttle valve: fully opened 3.5 - 4.7V
ABSOL TH´P/S+Engine: Idle Throttle valve: fully closed 0.0É
+Ignition switch: ON
(Engine stopped)Throttle valve: fully opened Approx. 80É
DTC P0120 THROTTLE POSITION SENSORQG
Component Description
EC-168

ECM Terminals and Reference Value=NJEC0081Specification 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.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
58 B Sensors' ground[Engine is running]
+Warm up condition
+Idle speedApproximately 0V
92 Y Throttle position sensor[Engine is running]
+Accelerator pedal fully released0.15 - 0.85V
[Ignition switch ªONº]
+Accelerator pedal fully depressed3.5 - 4.7V
111 R Sensors' power supply[Ignition switch ªONº]Approximately 5V
On Board Diagnosis LogicNJEC0082
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0120
0120An excessively low or high voltage from the sensor is
sent to ECM* while driving.+Harness or connectors
(The throttle position sensor circuit is open or
shorted.)
+Throttle position sensor
*: When this malfunction is detected, the ECM enters fail-safe mode and the MI lights up.
Fail-safe ModeNJEC0567
Detected items Engine operating condition in fail-safe mode
Throttle position sensor
circuitThrottle position will be determined based on the injected fuel amount and the engine speed.
Therefore, acceleration will be poor.
Condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
DTC Confirmation ProcedureNJEC0083NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:
+Before performing the following procedure, confirm that
battery voltage is more than 10V at idle.
+This test may be conducted with the drive wheels lifted in
DTC P0120 THROTTLE POSITION SENSORQG
ECM Terminals and Reference Value
EC-169

the shop or by driving the vehicle. If a road test is
expected to be easier, it is unnecessary to lift the vehicle.
SEF175Y
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and maintain the following conditions for at least
5 consecutive seconds.
VHCL SPEED SE More than 4 km/h (2 MPH)
Selector lever Suitable position except ªPº or ªNº
position
3) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-172.
With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0120 THROTTLE POSITION SENSORQG
DTC Confirmation Procedure (Cont'd)
EC-170

Diagnostic ProcedureNJEC0085
1 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
JEF104Y
©GO TO 2.
2 CHECK POWER SUPPLY
1. Disconnect throttle position sensor harness connector.
NEF309A
2. Turn ignition switch ªONº.
3. Check voltage between terminal 3 and ground with CONSULT-II or tester.
SEF306X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-6
+Harness for open or short between throttle position sensor terminal 3 and ECM terminal 111
©Repair harness or connectors.
DTC P0120 THROTTLE POSITION SENSORQG
Diagnostic Procedure
EC-172

4 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between throttle position sensor harness connector terminal 1 and engine ground.
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©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-6
+Harness for open or short between ECM terminal 58 and throttle position sensor
+Harness for open or short between ECM terminal 58 and TCM (Transmission Control Module)
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 92 and throttle position sensor harness connector terminal 2.
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 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK THROTTLE POSITION SENSOR
Refer to ªComponent Inspectionº, EC-174.
OK or NG
OK©GO TO 8.
NG©Replace throttle position sensor. To adjust it, perform ªBasic Inspectionº, EC-98.
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
DTC P0120 THROTTLE POSITION SENSORQG
Diagnostic Procedure (Cont'd)
EC-173