2001 NISSAN ALMERA o2 sensor

Freeze frame data
item*Description
S-FUEL TRIM-B1 [%]+ªShort-term fuel trimº at the moment a malfunction is detected is displayed.
+The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule.
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-87

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
HO2S2 MNTR (B1)
[RICH/LEAN]j+Display of heated oxygen sensor 2 (rear)
signal:
RICH ... means the amount of oxygen after
three way catalyst is relatively small.
LEAN ... means the amount of oxygen after
three way catalyst is relatively large.+When the engine is stopped, a cer-
tain value is indicated.
VHCL SPEED SE
[km/h] or [mph]jj+The vehicle speed computed from the
vehicle speed sensor signal is displayed.
BATTERY VOLT [V]j+The power supply voltage of ECM is dis-
played.
THRTL POS SEN [V]jj+The throttle position sensor signal voltage is
displayed.
FUEL T/TMP SE
[ÉC] or [ÉF]*+The fuel temperature judged from the fuel
tank temperature sensor signal voltage is
displayed.
INT/A TEMP SE
[ÉC] or [ÉF]j+The intake air temperature determined by
the signal voltage of the intake air tempera-
ture sensor is indicated.
EGR TEMP SEN [V]*jj+The signal voltage of the EGR temperature
sensor is displayed.
START SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition from the
starter signal.+After starting the engine, [OFF] is
displayed regardless of the starter
signal.
CLSD THL POS
[ON/OFF]jj+Indicates idle position [ON/OFF] computed
by ECM according to the throttle position
sensor signal.
CLSD THL/P SW
[ON/OFF]*j+Indicates mechanical contact [ON/OFF]
condition of the closed throttle position
switch.
AIR COND SIG
[ON/OFF]jj+Indicates [ON/OFF] condition of the air con-
ditioner switch as determined by the air
conditioning signal.
P/N POSI SW
[ON/OFF]jj+Indicates [ON/OFF] condition from the PNP
switch signal.
PW/ST SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition of the power
steering oil pressure switch determined by
the power steering oil pressure switch sig-
nal.
LOAD SIGNAL
[ON/OFF]jj+Indicates [ON/OFF] condition from the elec-
trical load signal and/or lighting switch.
ON ... rear defogger is operating and/or
lighting switch is on.
OFF ... rear defogger is not operating and
lighting switch is not on.
IGNITION SW
[ON/OFF]j+Indicates [ON/OFF] condition from ignition
switch.
HEATER FAN SW
[ON/OFF]j+Indicates [ON/OFF] condition from the
heater fan switch.
INJ PULSE-B1
[msec]j+Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.+When the engine is stopped, a cer-
tain computed value is indicated.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-88

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IGN TIMING [BTDC]j+Indicates the ignition timing computed by
ECM according to the input signals.
CAL/LD VALUE [%]+ªCalculated load valueº indicates the value
of the current airflow divided by peak air-
flow.
ABSOL TH.P/S [%]+ªAbsolute throttle position sensorº indicates
the throttle opening computed by ECM
according to the signal voltage of the
throttle position sensor.
MASS AIRFLOW
[gm/s]+Indicates the mass airflow computed by
ECM according to the signal voltage of the
mass air flow sensor.
IACV-AAC/V [step]j+Indicates the IACV-AAC valve control value
computed by ECM according to the input
signals.
PURG VOL C/V [%]+Indicates the EVAP canister purge volume
control solenoid valve computed by the
ECM according to the inpuct signals.
+The opening becomes larger as the value
increases.
EGR VOL CON/V
[step]*j+Indicates the EGR volume control valve
computed by the ECM according to the
input signals.
+The opening becomes larger as the value
increases.
SWRL CONT S/V
[ON/OFF]*+The control condition of the swirl control
valve control solenoid valve (determined by
ECM according to the input signals) is indi-
cated.
+ON ... Swirl control valve is closed.
OFF ... Swirl control valve is opened.
INT/V SOL-B1
[ON/OFF]+The control condition of the valve timing
solenoid valve (determined by ECM accord-
ing to the input signal) is indicated.
ON ... Intake valve timing control operating
OFF ... Intake valve timing control not oper-
ating
AIR COND RLY
[ON/OFF]j+Indicates the air conditioner relay control
condition determined by ECM according to
the input signals.
FUEL PUMP RLY
[ON/OFF]j+Indicates the fuel pump relay control condi-
tion determined by ECM according to the
input signals.
COOLING FAN
[ON/OFF]j+Indicates [ON/OFF] control condition of the
cooling fan determined by ECM according
to the input signals.
HO2S1 HTR (B1)
[ON/OFF]+Indicates [ON/OFF] condition of heated oxy-
gen sensor 1 heater (front) determined by
ECM according to the input signals.
HO2S2 HTR (B1)
[ON/OFF]+Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater (rear) determined by
ECM according to the input signals.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-89

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IDL A/V LEARN+Display the condition of idle air volume
learning
YET ... Idle air volume learning has not
been performed yet.
CMPLT ... Idle air volume learning has
already been performed successfully.
INCMP ... Idle air volume learning has not
been performed successfully.
TRVL AFTER MIL
[km] or [Mile]+Distance traveled while MI is activated
VOLTAGE [V]+Voltage measured by the voltage probe.
PULSE
[msec] or [Hz] or [%]+Pulse width, frequency or duty cycle mea-
sured by the pulse probe.+Only ª#º is displayed if item is
unable to be measured.
+Figures with ª#ºs are temporary
ones. They are the same figures as
an actual piece of data which was
just previously measured.
*: If so equipped
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
DATA MONITOR (SPEC) MODENJEC0034S11
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
MAS A/F SE-B1 [V]jj+The signal voltage of the mass air flow sen-
sor specification is displayed.+When the engine is running, speci-
fication range 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.+When the engine is running, speci-
fication range is indicated.
A/F ALPHA-B1 [%]j+Indicates the mean value of the air-fuel
ratio feedback correction factor per cycle.+When the engine is running, speci-
fication range is indicated.
+This data also includes the data for
the air-fuel ratio learning control.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODENJEC0034S07
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJECTION+Engine: Return to the original
trouble condition
+Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.+Harness and connector
+Fuel injectors
+Heated oxygen sensor 1 (front)
IGNITION TIMING+Engine: Return to the original
trouble condition
+Timing light: Set
+Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.+ªIdle Air Volume Leaningº (Refer
to EC-57.)
+Camshaft position sensor
(PHASE)
+Crankshaft position sensor
(POS)
+Engine component parts and
installing conditions
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
CONSULT-II (Cont'd)
EC-90

MEF036D
SEF233G
SEF234G
IntroductionNJEC0036The engine has an ECM to control major systems such as fuel
control, ignition control, idle air control system, etc. The ECM
accepts input signals from sensors and instantly drives actuators.
It is essential that both input and output signals are proper and
stable. At the same time, it is important that there are no problems
such as vacuum leaks, fouled spark plugs, or other problems with
the engine.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this
case, careful checking of suspected circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems. A road
test with CONSULT-II (or GST) or a circuit tester connected should
be performed. Follow the ªWork Flowº on EC-98.
Before undertaking actual checks, take a few minutes to talk with
a customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such problems, espe-
cially intermittent ones. Find out what symptoms are present and
under what conditions they occur. A ªDiagnostic Worksheetº like the
example on next page should be used.
Start your diagnosis by looking for ªconventionalº problems first.
This will help troubleshoot driveability problems on an electronically
controlled engine vehicle.
SEF907L
DIAGNOSTIC WORKSHEETNJEC0036S01There are many operating conditions that lead to the malfunction
of engine components. A good grasp of such conditions can make
trouble-shooting faster and more accurate.
In general, each customer feels differently about a problem. It is
important to fully understand the symptoms or conditions for a
customer complaint.
Utilize a diagnostic worksheet like the one on the next page in order
to organize all the information for troubleshooting.
Some conditions may cause the malfunction indicator lamp to
come on steady or blink and DTC to be detected.
Example:
Vehicle ran out of fuel, which caused the engine to misfire.
TROUBLE DIAGNOSIS Ð INTRODUCTIONQG
EC-96

DESCRIPTION FOR WORK FLOWNJEC0563S01
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using
the ªDIAGNOSTIC WORK SHEETº, EC-97.
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II or GST) the (1st trip) DTC
and the (1st trip) freeze frame data, then erase the DTC and the data. (Refer to EC-70, EC-73.) The (1st trip)
DTC and the (1st trip) freeze frame data can be used when duplicating the incident at STEP III & IV.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
Study the relationship between the cause, specified by (1st trip) DTC, and the symptom described by the cus-
tomer. (The ªSymptom Matrix Chartº will be useful. See EC-155.)
Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The ªDIAGNOSTIC WORK SHEETº and the freeze frame data are useful to verify the incident. Connect CON-
SULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the (1st trip) DTC by driving in (or performing) the ªDTC Confirmation Procedureº. Check and read
the (1st trip) DTC and (1st trip) freeze frame data by using CONSULT-II or GST.
During the (1st trip) DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO
TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
In case the ªDTC Confirmation Procedureº is not available, perform the ªOverall Function Checkº instead. The
(1st trip) DTC cannot be displayed by this check, however, this simplified ªcheckº is an effective alternative.
The ªNGº result of the ªOverall Function Checkº is the same as the (1st trip) DTC detection.
STEP VTake the appropriate action based on the results of STEP I through IV.
If the malfunction code is indicated, proceed to TROUBLE DIAGNOSIS FOR DTC PXXXX.
If the normal code is indicated, proceed refer to ªBASIC INSPECTIONº, EC-100. If CONSULT-II is available, per-
form ªDATA MONITOR (SPEC)º mode with CONSULT-II and proceed to the ªTROUBLE DIAGNOSIS Ð SPECI-
FICATION VALUEº. (Refer to EC-173.) (If malfunction is detected, proceed to ªREPAIR/REPLACEº.) Then per-
form inspections according to the Symptom Matrix Chart. (Refer to EC-155.)
STEP VIIdentify where to begin diagnosis based on the relationship study between symptom and possible causes.
Inspect the system for mechanical binding, loose connectors or wiring damage using (tracing) ªHarness Layoutsº.
Gently shake the related connectors, components or wiring harness with CONSULT-II set in ªDATA MONITOR
(AUTO TRIG)º mode.
Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CON-
SULT-II. Refer to EC-164.
The ªDiagnostic Procedureº in EC section contains a description based on open circuit inspection. A short circuit
inspection is also required for the circuit check in the Diagnostic Procedure. For details, refer to GI section
(ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº, ªCircuit Inspectionº).
Repair or replace the malfunction parts.
If malfunctioning part cannot be detected, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº,
EC-177.
STEP VIIOnce you have repaired the circuit or replaced a component, you need to run the engine in the same conditions
and circumstances which resulted in the customer's initial complaint.
Perform the ªDTC Confirmation Procedureº and confirm the normal code [DTC No. P0000] is detected. If the
incident is still detected in the final check, perform STEP VI by using a different method from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) (1st trip) DTC in
ECM and TCM (Transmission control module). (Refer to EC-70, EC-73.)
TROUBLE DIAGNOSIS Ð INTRODUCTIONQG
Work Flow (Cont'd)
EC-99

12 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-I
With CONSULT-II
1. Loosen throttle position sensor fixing bolts.
2. Confirm that proper vacuum is applied. Refer to test No. 10. During adjustment, vacuum should be applied.
3. Insert 0.05 mm (0.0020 in) feeler gauge between stopper and throttle drum as shown in the figure.
SEF073X
4. Turn throttle position sensor body counterclockwise until ªCLSD THL/P SWº signal switches to ªOFFº.
SEF863Y
©GO TO 13.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-105

13 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-II
With CONSULT-II
1. Temporarily tighten sensor body fixing bolts as follows.
+Gradually move the sensor body clockwise and stop it when ªCLSD THL/P SWº signal switches from ªOFFº to
ªONº, then temporarily tighten sensor body fixing bolts.
SEF964W
2. Make sure two or three times that the signal is ªONº when the throttle valve is closed and ªOFFº when it is opened.
3. Remove 0.05 mm (0.0020 in) feeler gauge then insert 0.15 mm (0.0059 in) feeler gauge.
4. Make sure two or three times that the signal remains ªOFFº when the throttle valve is closed.
5. Tighten throttle position sensor.
6. Check the ªCLSD THL/P SWº signal again.
SEF716Y
The signal remains ªOFFº while closing throttle valve.
OK or NG
OK©GO TO 14.
NG©GO TO 12.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-106