1998 NISSAN PICK-UP temperature sensor

VE
Check ``CO''%.
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Idle CO: 1.0 - 2.0% with engine runs smoothly.
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After checking ``CO''%
1. Touch ``BACK''.
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1. Disconnect the resistor from terminals of engine
coolant temperature sensor harness connector.
2. Connect engine coolant temperature sensor harness
connector to engine coolant temperature sensor.
NG OK
Replace heated oxygen sensor, set the diagnostic test mode II
(heated oxygen sensor monitor) and make sure that malfunction
indicator lamp goes on and off more than 5 times during 10 sec-
onds. (2,000 rpm, no-load)
NGOK
.
Connect heated oxygen sensor harness connector to heated
oxygen sensor.VF
Check fuel pressure regulator. Refer to EC-22.
Check mass air flow sensor and its circuit. Refer to EC-89.
Check injector and its circuit. Refer to EC-144.
Clean or replace if necessary.
Check engine coolant temperature sensor and its circuit. Refer
to EC-95.
Check ECM function* by substituting another known good
ECM.
*: ECM may be the cause of a problem, but
this is rarely the case.
VB
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BASIC SERVICE PROCEDUREKA
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment (Cont'd)
EC-30

Checking and adjusting idle speed, ignition timing
START
Visually check the following:
lAir cleaner clogging
lHoses and ducts for leaks
lElectrical connectors
lGasket
lThrottle valve and throttle position sensor operations
Start engine and warm it up until engine coolant temperature indi-
cator points to the middle of gauge and ensure that engine speed
is below 1,000 rpm.
Open engine hood and run engine at about 2,000 rpm for about 2
minutes under no-load.
Perform the diagnostic test mode II (Self-diagnostic results).
OKNG
Repair or replace components as neces-
sary.
.
Run engine at about 2,000 rpm for about 2 minutes under no-load.
Rev engine two or three times under no-load, then run engine for
about 1 minute at idle speed.
bVD
1. Select ``IGNITION TIMING ADJ'' in WORK SUPPORT
mode.
2. Touch ``START''.
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1. Stop engine and disconnect throttle position sensor har-
ness connector.
2. Start engine.
Rev engine (2,000 - 3,000 rpm) 2 or 3 times under no-load and run
engine at idle speed.
Check ignition timing with a timing light.
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10É 2É BTDC
OK NG
VAVB
SEF146U
SEF247F
SEF051PA
SEF248F
SEF546N
.
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.
.
..
BASIC SERVICE PROCEDUREKA
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment (Cont'd)
EC-32

DIAGNOSTIC TEST MODE IIÐHEATED OXYGEN SENSOR MONITOR
In this mode, the MALFUNCTION INDICATOR LAMP displays the condition of the fuel mixture (lean or rich)
which is monitored by the heated oxygen sensor.
MALFUNCTION INDICATOR LAMP Fuel mixture condition in the exhaust gasAir fuel ratio feedback control
condition
ON Lean
Closed loop control
OFF Rich
*Remains ON or OFF Any condition Open loop control
*: Maintains conditions just before switching to open loop.
To check the heated oxygen sensor function, start engine in the Diagnostic Test Mode II and warm it up
until engine coolant temperature indicator points to the middle of the gauge.
Next run engine at about 2,000 rpm for about 2 minutes under no-load conditions. Then make sure that the
MALFUNCTION INDICATOR LAMP comes ON more than 5 times every 10 seconds when measured at
2,000 rpm under no-load.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
Malfunction Indicator Lamp (MIL) (Cont'd)
EC-44

ECCS COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
WORK
SUPPORTSELF-DIAG-
NOSTIC
RESULTSDATA
MONITORACTIVE
TESTFUNCTION
TEST
ECCS COMPONENT PARTS
INPUT
Camshaft position sensor X X
Mass air flow sensor X X
Engine coolant temperature
sensorXXX
Heated oxygen sensor X
Vehicle speed sensor X X
Throttle position sensor X X X X
Intake air temperature sensor X X
Ignition switch (start signal) X X
Closed throttle position switch X X
Air conditioner switch X
Neutral position switch X X
Power steering oil pressure
switchXX
Battery voltage X
OUTPUT
Injectors X X X
Power transistor (Ignition timing) XX (Ignition
signal)XXX
IACV-AAC valve X X X X
Air conditioner relay X
Fuel pump relay X X X X
Swirl control valve control
solenoid valveXXX
EVAP canister purge control
solenoid valve*XXX
X: Applicable
* : This item is indicated as ``EGRC SOL/V'' on the CONSULT screen.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-47

SELF-DIAGNOSTIC MODE
Regarding items detected in ``SELF-DIAG RESULTS'' mode, refer to ``DIAGNOSTIC TROUBLE CODE
INDEX'', EC-1.
DATA MONITOR MODE
Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
CMPSRPM
(POS) [rpm]
jj
lIndicates the engine speed computed
from the POS signal (1É signal) of the
camshaft position sensor.
MAS AIR/FL SE [V]
jjlThe signal voltage of the mass air flow
sensor is displayed.lWhen the engine is stopped, a certain
value is indicated.
COOLAN TEMP/S
[ÉC] or [ÉF]
jj
lThe engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is displayed.lWhen the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine coolant
temperature determined by the ECM is
displayed.
O2 SEN [V]
jjlThe signal voltage of the heated oxygen
sensor is displayed.lLHD models only
M/R F/C MNT
[RICH/LEAN]
jj
lDisplay of heated oxygen sensor signal
during air-fuel ratio feedback control:
RICH ... means the mixture became
``rich'', and control is being affected
toward a leaner mixture.
LEAN ... means the mixture became
``lean'', and control is being affected
toward a rich mixture.lAfter turning ON the ignition switch,
``RICH'' is displayed until air-fuel mixture
ratio feedback control begins.
lWhen the air-fuel ratio feedback is
clamped, the value just before the clamp-
ing is displayed continuously.
lLHD models only
VHCL SPEED SE
[km/h] or [mph]
jjlThe vehicle speed computed from the
vehicle speed sensor signal is displayed.
BATTERY VOLT [V]
jjlThe power supply voltage of ECM is dis-
played.
THRTL POS SEN [V]
jjlThe throttle position sensor signal volt-
age is displayed.
INT/A TEMP SE
[ÉC] or [ÉF]
j
lThe intake air temperature (determined
by the signal voltage of the intake air
temperature sensor) is indicated.
START SIGNAL
[ON/OFF]
jjlIndicates [ON/OFF] condition from the
starter signal.lAfter starting the engine, [OFF] is
displayed regardless of the starter signal.
CLSD THL/POSI
[ON/OFF]
jj
lIndicates [ON/OFF] condition from the
throttle position sensor signal.
AIR COND SIG
[ON/OFF]
jj
lIndicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]
jj
lIndicates [ON/OFF] condition from the
park/neutral position switch signal.
PW/ST SIGNAL
[ON/OFF]
jj
l[ON/OFF] condition of the power steering
oil pressure switch determined by the
power steering oil pressure signal is indi-
cated.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-48

ACTIVE TEST MODE
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJECTION
lEngine: Return to the original trouble
condition
lChange the amount of fuel injection
using CONSULT.If trouble symptom disappears, see
CHECK ITEM.
lHarness and connectorlFuel injectorslHeated oxygen sensor
IACV-AAC/V
OPENING
lEngine: After warming up, idle the
engine.
lChange the IACV-AAC valve opening
percent using CONSULT.Engine speed changes according to the
opening percent.lHarness and connectorlIACV-AAC valve
ENG COOLANT
TEMP
lEngine: Return to the original trouble
condition
lChange the engine coolant
temperature using CONSULT.If trouble symptom disappears, see
CHECK ITEM.
lHarness and connectorlEngine coolant temperature sensorlFuel injectors
IGNITION TIMING
lEngine: Return to the original trouble
condition
lTiming light: SetlRetard the ignition timing using
CONSULT.If trouble symptom disappears, see
CHECK ITEM.
lAdjust ignition timing (by moving
camshaft position sensor)
POWER BALANCE
lEngine: After warming up, idle the
engine.
lA/C switch ``OFF''lShift lever ``N''lCut off each injector signal one at a
time using CONSULT.Engine runs rough or dies.
lHarness and connectorlCompressionlInjectorslIgnition coil with power transistorlSpark plugs
FUEL PUMP RELAY
lIgnition switch: ON (Engine stopped)lTurn the fuel pump relay ``ON'' and
``OFF'' using CONSULT and listen to
operating sound.Fuel pump relay makes the operating
sound.lHarness and connectorlFuel pump relay
EGRC SOLENOID
VALVE
(EVAP canister
purge control
solenoid valve)
lIgnition switch: ONlTurn solenoid valve ``ON'' and ``OFF''
with CONSULT and listen to
operating sound.Solenoid valve makes an operating
sound.lHarness and connectorlEVAP canister purge control solenoid
valve
SWIRL CONT SOL
VALVE
lIgnition switch: ON (Engine stopped)lTurn solenoid valve ``ON'' and ``OFF''
with CONSULT and listen to
operating sound.Solenoid valve makes an operating
sound.lHarness and connectorlSwirl control valve control solenoid
valve
SELF-LEARNING
CONT
lIn this test, the coefficient of self-learning control mixture ratio returns to the original coefficient by touching ``CLEAR'' on the
screen.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-50

FUNCTION TEST MODE
FUNCTION TEST
ITEMCONDITION JUDGEMENT CHECK ITEM (REMEDY)
SELF-DIAG
RESULTS
lIgnition switch: ON
(Engine stopped)
lDisplays the results of on board
diagnostic system.Ð Objective system
CLOSED THROTTLE
POSI
lIgnition switch: ON
(Engine stopped)
lThrottle position sensor circuit is
tested when throttle is opened
and closed fully. (``IDLE
POSITION'' is the test item name
for the vehicles in which idle is
selected by throttle position
sensor.)Throttle valve:
openedOFF
lHarness and connector
lThrottle position sensor (Closed
throttle position)
lThrottle position sensor (Closed
throttle position) adjustment
lThrottle linkage
lVerify operation in DATA
MONITOR mode. Throttle valve:
closedON
THROTTLE POSI
SEN CKT
lIgnition switch: ON
(Engine stopped)
lThrottle position sensor circuit is
tested when throttle is opened
and closed fully.Range (Throttle
valve fully opened
Ð Throttle valve
fully closed)More than
3.0V
lHarness and connector
lThrottle position sensor
lThrottle position sensor
adjustment
lThrottle linkage
lVerify operation in DATA
MONITOR mode.
PARK/NEUT POSI
SW CKT
lIgnition switch: ON
(Engine stopped)
lNeutral position switch circuit is
tested when shift lever is
manipulated.Out of N/P
positionsOFF
lHarness and connector
lNeutral position switch
lLinkage adjustment
In N/P positions ON
FUEL PUMP
CIRCUIT
lIgnition switch: ON
(Engine stopped)
lFuel pump circuit is tested by
checking the pulsation in fuel
pressure when fuel tube is
pinched.There is pressure pulsation on
the fuel feed hose.
lHarness and connector
lFuel pump
lFuel pump relay
lFuel filter clogging
lFuel level
EGRC SOL/V
CIRCUIT
(EVAP canister purge
control solenoid valve
circuit)
lIgnition switch: ON
(Engine stopped)
lEVAP canister purge control
solenoid valve circuit is tested by
checking solenoid valve operating
noise.The solenoid valve makes an
operating sound every 3
seconds.lHarness and connector
lEVAP canister purge control
solenoid valve
START SIGNAL
CIRCUIT
lIgnition switch: ON®START
lStart signal circuit is tested when
engine is started by operating the
starter. Battery voltage and water
temperature before cranking, and
average battery voltage, mass air
flow sensor output voltage and
cranking speed during cranking
are displayed.Start signal: OFF®ON
lHarness and connector
lIgnition switch
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-51

Fail-Safe Chart
The ECM enters fail-safe mode, if any of the following malfunctions are detected due to the open or short
circuit.
When the ECM enters the ECM fail-safe mode listed in the last column below, the MIL illuminates.
DTC No.Detected
itemsEngine operating condition in fail-safe mode
12Mass air
flow sensor
circuitEngine speed will not rise more than 2,400 rpm due to the fuel cut.
13 Engine cool-
ant tempera-
ture sensor
circuitEngine coolant temperature will be determined by ECM based on the time after turning ignition switch
``ON'' or ``START''.
CONSULT displays the engine coolant temperature decided by ECM.
41 Intake air
temperature
sensor cir-
cuitThe ECM controls on the assumption that the intake air temperature is 20ÉC (68ÉF).
43 Throttle
position sen-
sor circuitThrottle position will be determined based on the amount of mass air flow and the engine speed.
Therefore, acceleration will be poor.
Unable to
access Diag-
nostic Test
Mode IIECMECM fail-safe activating condition
The computing function of the ECM was judged to be malfunctioning.
When the fail-safe system activates, i.e. if the ECM detects a malfunction condition in the CPU of
ECM, the MALFUNCTION INDICATOR LAMP on the instrument panel lights to warn the driver.
However, it is not possible to access ECCS and DTC cannot be confirmed.
Engine control with ECM fail-safe
When the fail-safe system is operating, fuel injection, ignition timing, fuel pump operation and IACV-
AAC valve operation are controlled under certain limitations.
Replace ECM, if ECM fail-safe condition is confirmed.
ConditionEngine coolant temperature decided
(CONSULT display)
Just as ignition switch is turned ON or START 20ÉC (68ÉF)
More than 6 minutes after ignition START 80ÉC (176ÉF)
Except as shown above20 - 80ÉC (68 - 176ÉF)
(Depends on the time)
Driving condition
When engine is idling Normal
When accelerating Poor acceleration
ECM fail-safe operation
Engine speed Engine speed will not rise more than 3,000 rpm.
Fuel injection Simultaneous multiport fuel injection system
Ignition timing Ignition timing is fixed at the preset value.
Fuel pumpFuel pump relay is ``ON'' when engine is running and ``OFF'' when
engine stalls.
IACV-AAC valve Full open
TROUBLE DIAGNOSIS Ð General DescriptionKA
EC-61