2001 NISSAN ALMERA engine

With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 9 seconds, then
turn ªONº.
3) Select ªMODE 1º with GST and maintain the following condi-
tions for at least 5 consecutive seconds.
Engine speed Above 2,400 rpm
Vehicle speed Above 90 km/h (56 MPH)
Selector lever 4th or 5th
4) Select ªMODE 7º with GST
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-423.
DTC P1401 EGR TEMPERATURE SENSOR (WHERE FITTED)QG
DTC Confirmation Procedure (Cont'd)
EC-420

Wiring DiagramNJEC0346SEDAN MODELS AND HATCHBACK MODELS WITH
ECM IN ENGINE COMPARTMENT
NJEC0346S01
HEC807
DTC P1401 EGR TEMPERATURE SENSOR (WHERE FITTED)QG
Wiring Diagram
EC-421

Diagnostic ProcedureNJEC0347
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect EGR temperature sensor harness connector.
SEF127X
3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and ground with CONSULT-II or tester.
SEF945X
OK or NG
OK©GO TO 2.
NG©Repair harness or connectors.
2 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between EGR temperature sensor harness 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 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between EGR temperature sensor and ECM
+Harness for open or short between TCM (Transmission Control Module) and ECM
+Joint connector-3 (If so equipped)
+Joint connector-6 (If so equipped)
©Repair open circuit or short to ground or short to power in harness or connector.
DTC P1401 EGR TEMPERATURE SENSOR (WHERE FITTED)QG
Diagnostic Procedure
EC-423

DescriptionNJEC0349SYSTEM DESCRIPTIONNJEC0349S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
EGR vol-
ume controlEGR volume control valve Camshaft position sensor (PHASE) Engine speed and cylinder number
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle position
Vehicle speed sensor Vehicle speed
Battery Battery voltage
This system controls flow rate of EGR led from exhaust manifold
to intake manifold. The opening of the EGR by-pass passage in the
EGR volume control valve changes to control the flow rate. A
built-in step motor moves the valve in steps corresponding to the
ECM output pulses. The opening of the valve varies for optimum
engine control. The optimum value stored in the ECM is determined
by considering various engine conditions. The EGR volume control
valve remains close under the following conditions.
+Extremely light load engine operation
+Mass air flow sensor malfunction
+Engine idling
+Low engine coolant temperature
+Excessively high engine coolant temperature
+High-speed engine operation
+Wide open throttle
+Low battery voltage
+Engine starting
SEF551W
DTC P1402 EGR FUNCTION (OPEN) (WHERE FITTED)QG
Description
EC-425

SEF552W
COMPONENT DESCRIPTIONNJEC0349S02EGR Volume Control ValveNJEC0349S0201The EGR volume control valve uses a step motor to control the flow
rate of EGR from exhaust manifold. This motor has four winding
phases. It operates according to the output pulse signal of the
ECM. Two windings are turned ON and OFF in sequence. Each
time an ON pulse is issued, the valve opens or closes, changing
the flow rate. When no change in the flow rate is needed, the ECM
does not issue the pulse signal. A certain voltage signal is issued
so that the valve remains at that particular opening.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0539Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
EGR TEMP SEN+Engine: After warming up Less than 4.5V
EGR VOL CON/V+Engine: After warming up
+Air conditioner switch: ªOFFº
+Shift lever: ªNº
+No-loadIdle 0 step
Revving engine up to 3,000 rpm
quickly10 - 55 step
ECM Terminals and Reference ValueNJEC0540Specification 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)
8
9
17
18SB
W/B
R/Y
BR/REGR volume control valve[Engine is running.]
+Warm-up condition
+Idle speed0 - 14V
58 B Sensor's ground[Engine is running.]
+Warm-up condition
+Idle speed0V
72 P/B EGR temperature sensor[Engine is running.]
+Warm-up condition
+Idle speedLess than 4.5V
[Engine is running.]
+Warm-up condition
+EGR system is operating.0 - 1.0V
SEF073P
On Board Diagnosis LogicNJEC0350If EGR temperature sensor detects EGR flow under the condition
that does not call for EGR, a high-flow malfunction is diagnosed.
NOTE:
Diagnosis for this DTC will occur when engine coolant temperature
is below 50 to 60ÉC (122 to 140ÉF). Therefore, it will be better to
turn ignition switch ªONº (start engine) at the engine coolant tem-
perature below 30ÉC (86ÉF) when starting DTC confirmation pro-
cedure.
DTC P1402 EGR FUNCTION (OPEN) (WHERE FITTED)QG
Description (Cont'd)
EC-426

DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P1402
1402+EGR flow is detected under conditions that do not call for
EGR.+Harness or connectors
(The valve circuit is open or shorted.)
+EGR volume control valve leaking or stuck open
+EGR temperature sensor
SEF202Y
SEF851Y
SEF852Y
SEF236Y
DTC Confirmation ProcedureNJEC0351NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
+Always perform at a temperature above þ10ÉC (14ÉF).
+Engine coolant temperature and EGR temperature must
be verified in ªDATA MONITORº mode with CONSULT-II
before starting DTC WORK SUPPORT test. If it is out of
range below, the test cannot be conducted.
COOLAN TEMP/S: þ10 to 40ÉC (14 to 104ÉF)*
EGR TEMP SEN: Less than 4.8V
If the values are out of the ranges indicated above, park
the vehicle in a cool place and allow the engine tempera-
ture to stabilize. Do not attempt to reduce the engine cool-
ant or EGR temperature with a fan or means other than
ambient air. Doing so may produce an inaccurate diagnos-
tic result.
*: Although CONSULT-II screen displays ªþ10 to 40ÉC (14 to
104ÉF)º as a range of engine coolant temperature, ignore it.
With CONSULT-II
1) Turn ignition switch ªOFFº and wait at least 9 seconds, then
turn ignition switch ªONº.
2) Select ªEGR SYSTEM P1402º of ªEGR SYSTEMº in ªDTC
WORK SUPPORTº mode with CONSULT-II.
3) Touch ªSTARTº. Follow instruction of CONSULT-II.
4) Start engine and let it idle until ªTESTINGº on CONSULT-II
screen is turned to ªCOMPLETEDº. (It will take 45 seconds or
more.)
If ªTESTINGº is not displayed after 5 minutes, turn ignition
ªOFFº and cool the engine coolant temperature to the
range of þ10 to 40ÉC (14 to 104ÉF). Retry from step 1.
5) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº. If ªNGº is displayed, refer to ªDiagnostic
Procedureº, EC-431.
DTC P1402 EGR FUNCTION (OPEN) (WHERE FITTED)QG
On Board Diagnosis Logic (Cont'd)
EC-427

SEF947X
With GST
1) Turn ignition switch ªONº and select ªMODE 1º with GST.
2) Check that engine coolant temperature is within the range of
þ10 to 40ÉC (14 to 104ÉF).
3) Check that voltage between ECM terminal 72 (EGR tempera-
ture sensor signal) and ground is less than 4.8V.
4) Start engine and let it idle for at least 45 seconds.
5) Stop engine.
6) Perform from step 1 to 4.
7) Select ªMODE 3º with GST.
8) If DTC is detected, go to ªDiagnostic Procedureº, EC-431.
+When using GST, ªDTC Confirmation Procedureº should
be performed twice as much as when using CONSULT-II
because GST cannot display MODE 7 (1st trip DTC) con-
cerning this diagnosis. Therefore, using CONSULT-II is
recommended.
DTC P1402 EGR FUNCTION (OPEN) (WHERE FITTED)QG
DTC Confirmation Procedure (Cont'd)
EC-428

Wiring DiagramNJEC0352SEDAN MODELS AND HATCHBACK MODELS WITH
ECM IN ENGINE COMPARTMENT
NJEC0352S01
HEC794
DTC P1402 EGR FUNCTION (OPEN) (WHERE FITTED)QG
Wiring Diagram
EC-429