2001 NISSAN ALMERA N16 Idle control valve

System DescriptionNJEC0015S02
SEF742M
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of
the engine. The ignition timing data is stored in the ECM. This data forms the map shown above.
The ECM receives information such as the injection pulse width, crankshaft position sensor signal and cam-
shaft position sensor signal. Computing this information, ignition signals are transmitted to the power transis-
tor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
AÉBTDC
During the following conditions, the ignition timing is revised by the ECM according to the other data stored
in the ECM.
+At starting
+During warm-up
+At idle
+During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions.
If engine knocking occurs, the knock sensor monitors the condition. The signal is transmitted to the ECM. The
ECM retards the ignition timing to eliminate the knocking condition.
Air Conditioning Cut Control
DESCRIPTIONNJEC0016Input/Output Signal ChartNJEC0016S01
Sensor Input Signal to ECMECM func-
tionActuator
Air conditioner switch Air conditioner ªONº signal
Air condi-
tioner cut
controlAir conditioner relay PNP switch Neutral position
Throttle position sensor Throttle valve opening angle
Crankshaft position sensor (POS) Engine speed
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Refrigerant pressure sensor Refrigerant pressure
Vehicle speed sensor Vehicle speed
Power steering oil pressure switch Power steering operation
System DescriptionNJEC0016S02This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
+When the accelerator pedal is fully depressed.
+When cranking the engine.
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONQG
Electronic Ignition (EI) System (Cont'd)
EC-32

Positive Crankcase Ventilation
DESCRIPTIONNJEC0022
SEF921W
This system returns blow-by gas to the intake collector.
The positive crankcase ventilation (PCV) valve is provided to conduct crankcase blow-by gas to the intake
manifold.
During partial throttle operation of the engine, the intake manifold sucks the blow-by gas through the PCV
valve.
Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of ventilating air.
The ventilating air is then drawn from the air duct into the crankcase. In this process the air passes through
the hose connecting air inlet tubes to rocker cover.
Under full-throttle condition, the manifold vacuum is insufficient to draw the blow-by flow through the valve.
The flow goes through the hose connection in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not meet the requirement. This is because some
of the flow will go through the hose connection to the intake collector under all conditions.
SEF244Q
INSPECTIONNJEC0023PCV (Positive Crankcase Ventilation) ValveNJEC0023S01With engine running at idle, remove PCV valve from breather sepa-
rator. A properly working valve makes a hissing noise as air passes
through it. A strong vacuum should be felt immediately when a fin-
ger is placed over the valve inlet.
ET277
Ventilation HoseNJEC0023S021. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any
hose cannot be freed of obstructions, replace.
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONQG
Positive Crankcase Ventilation
EC-37

Freeze frame data
item*Description
ENGINE SPEED
[rpm]+The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph]+The vehicle speed at the moment a malfunction is detected is displayed.
ABSOL TH´P/S [%]+The throttle valve opening angle at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]+The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE [ÉC]
or [ÉF]+The intake air temperature at the moment a malfunction is detected is displayed.
*: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODENJEC0034S06
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]jj+Indicates the engine speed computed from
the POS signal of the crankshaft position
sensor.+Accuracy becomes poor if engine
speed drops below the idle rpm.
+If the signal is interrupted while the
engine is running, an abnormal
value may be indicated.
MAS A/F SE-B1 [V]jj+The signal voltage of the mass air flow sen-
sor is displayed.+When the engine is stopped, a cer-
tain value is indicated.
B/FUEL SCHDL
[msec]+ªBase fuel scheduleº indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board correc-
tion.
A/F ALPHA-B1 [%]j+Indicates the mean value of the air-fuel
ratio feedback correction factor per cycle.+When the engine is stopped, a cer-
tain value is indicated.
+This data also includes the data for
the air-fuel ratio learning control.
COOLAN TEMP/S
[ÉC] or [ÉF]jj+The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is displayed.+When the engine coolant tempera-
ture sensor is open or short-
circuited, ECM enters fail-safe
mode. The engine coolant tempera-
ture determined by the ECM is dis-
played.
HO2S1 (B1) [V]jj+The signal voltage of the heated oxygen
sensor 1 (front) is displayed.
HO2S2 (B1) [V]j+The signal voltage of the heated oxygen
sensor 2 (rear) is displayed.
HO2S1 MNTR (B1)
[RICH/LEAN]j+Display of heated oxygen sensor 1 (front)
signal during air-fuel ratio feedback control:
RICH ... means the mixture became ªrichº,
and control is being affected toward a
leaner mixture.
LEAN ... means the mixture became ªleanº,
and control is being affected toward a rich
mixture.+After turning ON the ignition switch,
ªRICHº is displayed until air-fuel
mixture ratio feedback control
begins.
+When the air-fuel ratio feedback is
clamped, the value just before the
clamping is displayed continuously.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-85

TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
IACV-AAC/V
OPENING+Engine: After warming up, idle
the engine.
+Change the IACV-AAC valve
opening steps using CONSULT-
II.Engine speed changes according
to the opening steps.+Harness and connector
+IACV-AAC valve
POWER BAL-
ANCE+Engine: After warming up, idle
the engine.
+Air conditioner switch ªOFFº
+Shift lever ªNº
+Cut off each injector signal one
at a time using CONSULT-II.Engine runs rough or dies.+Harness and connector
+Compression
+Injectors
+Power transistor
+Spark plugs
+Ignition coils
COOLING FAN+Ignition switch: ON
+Turn the cooling fan ªONº and
ªOFFº using CONSULT-II.Cooling fan moves and stops.+Harness and connector
+Cooling fan motor
ENG COOLANT
TEMP+Engine: Return to the original
trouble condition
+Change the engine coolant tem-
perature indication using CON-
SULT-II.If trouble symptom disappears, see
CHECK ITEM.+Harness and connector
+Engine coolant temperature sen-
sor
+Fuel injectors
FUEL PUMP
RELAY+Ignition switch: ON
(Engine stopped)
+Turn the fuel pump relay ªONº
and ªOFFº using CONSULT-II
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.+Harness and connector
+Fuel pump relay
EGR VOL
CONT/V
(If so equipped)+Engine: After warming up, idle
the engine.
+Change the EGR volume control
valve opening step using CON-
SULT-II.Engine speed changes according
to the opening step.+Harness and connector
+EGR volume control valve
VALVE TIMING
SOL+Ignition switch: ON
+Turn intake valve timing control
solenoid valve ªONº and ªOFFº
using CONSULT-II and listen for
operating sound.Intake valve timing control solenoid
valve makes an operating sound.+Harness and connector
+Intake valve timing control sole-
noid valve
PURG VOL
CONT/V+Engine: After warming up, idle
the engine.
+Change the EVAP canister
purge volume control solenoid
valve opening percent using
CONSULT-II.Engine speed changes according
to the opening percent.+Harness and connector
+EVAP canister purge volume
control solenoid valve
DTC AND SRT CONFIRMATION MODENJEC0034S08This mode is not available for models without Euro-OBD system.
SRT STATUS ModeNJEC0034S0801For details, refer to ªSYSTEM READINESS TEST (SRT) CODEº,
EC-60.
SRT Work Support ModeNJEC0034S0803This mode enables a technician to drive a vehicle to set the SRT
while monitoring the SRT status.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-89

Symptom Matrix ChartNJEC0041SYSTEM Ð ENGINE CONTROL SYSTEMNJEC0041S01
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit11232 22 3 2EC-464
Fuel pressure regulator sys-
tem334444444 4EC-39
Injector circuit11232 22 2EC-447
Evaporative emission sys-
tem334444444 4EC-33
Air Positive crankcase ventila-
tion system334444444 41EC-37
Incorrect idle speed adjust-
ment3 3 1 1 1 1 1 EC-41
IACV-AAC valve circuit112332222 2 2EC-313
Ignition Incorrect ignition timing
adjustment33111 11 1EC-41
Ignition circuit11222 22 2EC-451
EGR EGR volume control valve
circuit2233 3EC-293
EGR system212333223 3EC-285,
293, 353
Main power supply and ground circuit22333 33 23 2EC-145
Air conditioner circuit223333333 3 2HAsection
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
Symptom Matrix Chart
EC-124

CONSULT-II Reference Value in Data Monitor
Mode
NJEC0042Remarks:
+Specification data are reference values.
+Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
(i.e., Adjust ignition timing with a timing light before monitoring IGN TIMING. Specification data might be displayed even when igni-
tion timing is not adjusted to specification. This IGN TIMING monitors the data calculated by the ECM according to the input signals
from the crankshaft position sensor and other ignition timing related sensors.)
+If the real-time diagnosis results are NG, and the on board diagnostic system results are OK, when diagnosing the mass air flow sensor,
first check to see if the fuel pump control circuit is normal.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED+Tachometer: Connect
+Run engine and compare tachometer indication with the CONSULT-II
value.Almost the same speed as the
CONSULT-II value.
MAS A/F SE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 1.0 - 1.7V
2,500 rpm 1.5 - 2.1V
B/FUEL SCHDL+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 1.5 - 3.0 msec
2,000 rpm 1.2 - 3.0 msec
A/F ALPHA-B1+Engine: After warming upMaintaining engine speed at 2,000
rpm75 - 125%
COOLAN TEMP/S+Engine: After warming up More than 70ÉC (158ÉF)
HO2S1 (B1)
+Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V¨0.6 - 1.0V
HO2S1 MNTR (B1)LEAN¨RICH
Changes more than 5 times
during 10 seconds.
HO2S2 (B1)
+Engine: After warming upRevving engine from idle to 3,000
rpm quickly0 - 0.3V¨0.6 - 1.0V
HO2S2 MNTR (B1)LEAN¨RICH
VHCL SPEED SE+Turn drive wheels and compare speedometer indication with the CON-
SULT-II valueAlmost the same speed as the
CONSULT-II value
BATTERY VOLT+Ignition switch: ON (Engine stopped) 11 - 14V
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
EGR TEMP SEN*+Engine: After warming up Less than 4.5V
START SIGNAL+Ignition switch: ON®START®ON OFF®ON®OFF
CLSD THL POS
CLSD THL/P SW*+Engine: Idle Throttle valve: Idle position ON
+Ignition switch: ON
(Engine stopped)Throttle valve: Slightly open OFF
AIR COND SIG+Engine: After warming up, idle
the engineA/C switch ªOFFº OFF
A/C switch ªONº
(Compressor operates)ON
P/N POSI SW+Ignition switch: ONShift lever ªPº or ªNº ON
Except above OFF
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
CONSULT-II Reference Value in Data Monitor Mode
EC-128

TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
3 W/RHeated oxygen sensor 2
heater (rear)[Engine is running]
+Engine speed is below 3,600 rpm
+After driving for 2 minutes at a speed of 70
km/h (43 MPH) or moreApproximately 0.7V
[Ignition switch ªONº]
+Engine stopped
+Engine speed is above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
4 R/BHeated oxygen sensor 1
heater (front)[Engine is running]
+Engine speed is below 3,200 rpmApproximately 0V
[Engine is running]
+Engine speed is above 3,200 rpmBATTERY VOLTAGE
(11 - 14V)
6
7
15
16BR
L/G
P
ORIACV-AAC valve[Engine is running]
+Warm-up condition
+Idle speed0.1 - 14V
8*
9*
17*
18*SB
W/B
R/Y
BR/REGR volume control
valve[Engine is running]
+Warm-up condition
+Rev engine from 2,000 to 4,000 rpm0 - 14V
10 Y/B A/T signal No. 3[Engine is running]
+Idle speedApproximately 0V
13 LG/R Cooling fan relay[Engine is running]
+Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fan is operatingApproximately 0V
14 GY/LEVAP canister purge
volume control valve
(ON/OFF duty)[Engine is running]
+Warm-up condition
+Accelerator pedal depressed5 - 12V
SEF975W
19 BR/W A/T signal No. 5[Engine is running]
+Idle speedApproximately 8V
21 B/P Fuel pump relay[Ignition switch ªONº]
+For 1 second after turning ignition switch
ªONº
[Engine is running]0-1V
[Ignition switch ªONº]
+More than 1 second after turning ignition
switch ªONºBATTERY VOLTAGE
(11 - 14V)
22 OR/L Malfunction indicator[Ignition switch ªONº]0-1V
[Engine is running]
+Idle speedBATTERY VOLTAGE
(11 - 14V)
23 L Air conditioner relay[Engine is running]
+Both A/C switch and blower switch are ªONºApproximately 0V
[Engine is running]
+A/C switch is ªOFFºBATTERY VOLTAGE
(11 - 14V)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
ECM Terminals and Reference Value (Cont'd)
EC-134

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