
ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION
CONSULT (ConI'd)
SELF-DIAGNOSTIC MODE
Regarding itemsdetected in"SELF-DIAG RESULTS"mode,referto"Diagnostic TroubleCode(DTC)
Chart" (RefertoEC-62.)
DATA MONITOR MODE
Monitored item ECM
Main
[Unit] input
signals Description
Remarks
signals
CMPS.RPM •Indicates theengine speedcomputed •Accuracy becomespoorifengine
(REF) [rpm]
00
from
theREF signal (180'signal) of
speeddropsbelow theidle rpm.
the camshaft positionsensor.
•Ifthe signal isinterrupted whilethe
engine isrunning, anabnormal value
may beindicated .
MAS AIR/FL SE[V]
0 0
•
The signal voltage ofthe mass air
•When theengine isstopped, acertain
flow sensor isdisplayed .
valueisindicated.
COOLAN TEMP/S
•The engine coolant temperature •When theengine coolant temperature
['C] or['F]
00
(determined
bythe signal voltage of
sensorisopen orshort-circuited,
the engine coolant temperature sen-ECMenters fail-safe mode.The
sor) isdisplayed.
enginecoolant temperature deter-
mined bythe ECM isdisplayed .
02 SENSOR [V]
00
•
The signal voltage ofthe oxygen sen-
sor*1 isdisplayed .
M/R F/CMNT •
Display ofoxygen sensorsignaldur-
•After turning ONthe ignition switch,
[RICH/LEAN] ingair-fuel ratiofeedback control: "RICH"isdisplayed untilair-fuel mix-
RICH ...means themixture became
tureratio feedback controlbegins.
0 0
"rich",
andcontrol isbeing affected •When theair-fuel ratiofeedback is
toward aleaner mixture.
clamped,thevalue justbefore the
LEAN ...means themixture became clampingisdisplayed continuously.
"lean", andcontrol isbeing affected
toward arich mixture .
VHCL SPEED SE
00
•
The vehicle speedcomputed fromthe
[km/h] or[mph] vehicle
speedsensor signalisdis-
played .
BATTERY VOLT[V]
0 0
•
The power supply voltage ofECM is
displayed .
THRTL POSSEN[V]
0 0
•
The throttle position sensorsignal
voltage isdisplayed.
INT/A TEMP SE['C] •The intake airtemperature deter-
or ['F]*2
0
mined
bythe signal voltage ofthe
intake airtemperature sensorisindi-
cated .
START SIGNAL
00
•
Indicates [ON/OFF] conditionfromthe•After starting theengine, [OFF]isdis-
[ON/OFF] startersignal. playedregardless ofthe starter sig-
nal.
CLSD THLIPOSI •Indicates theclosed throttle position
[ON/OFF]
00
[ON/OFF]
determined bythe throttle
position sensorsignal.
ON: Closed throttle position
OFF: Other thanclosed throttle position
AIR COND SIG
00
•
Indicates [ON/OFF] conditionofthe
[ON/OFF] air
conditioner switchasdetermined
by the airconditioning signal.
PIN POSI SW
00
•
Indicates [ON/OFF] conditionfromthe
[ON/OFF] park/neutralpositionswitchsignal.
PW/ST SIGNAL •
Indicates [ON/OFF] conditionofthe
[ON/OFF]
00
power
steering oilpressure switch
determined bythe power steering oil
pressure signal.
NOTE:
Any monitored itemthatdoes notmatch thevehicle beingdiagnosed isdeleted fromthedisplay auto-
matically.
*1: Heated oxygen sensor(ForEurope andIsrael, andAustralia A/Tmodels)
Oxygen sensor(Except forEurope andIsrael, andAustralia A/Tmodels)
*2: For Australia
EC-51
•

ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION
CONSULT (Cont'd)
ACTIVE TESTMODE
TEST ITEM CONDITION JUDGEMENT
CHECKITEM(REMEDY)
• Engine: Returntothe original
•Harness andconnector
FUEL INJECTION trouble
condition If
trouble symptom disappears,
•Fuel injectors
• Change theamount offuel see
CHECK ITEM.
injection usingCONSULT . •
Oxygen sensor*1
• Engine: Afterwarming up,idle
IACV-AACIV the
engine.
Enginespeedchanges according •Harness andconnector
OPENING •
Change theIACV-AAC valve
tothe opening percent. •
IACV-AAC valve
opening percentusingCON-
SULT.
• Engine: Returntothe original
•Harness andconnector
ENG COOLANT trouble
condition
Iftrouble symptom disappears, •
Engine coolant temperature
TEMP •
Change theengine coolant
.
see CHECK ITEM. sensor
temperature indicationusing
•Fuel injectors
CONSULT.
• Engine: Returntothe original
trouble condition
Iftrouble symptom disappears,
IGNITION TIMING•
Timing light:Set •
Adjust initialignition timing
• Retard theignition timingusingsee
CHECK ITEM.
CONSULT .
• Engine: Afterwarming up,idle •
Harness andconnector
the engine. •
Compression
POWER •
A/C switch "OFF"
Enginerunsrough ordies . •
Injectors
BALANCE •
Shift lever "N" •
Power transistor
• Cut offeach injector signalone •
Spark plugs
at atime using CONSULT. •
Ignition coils
• Ignition switch:ON
COOLING FAN*3•
Turn thecooling fan"ON" and
Cooling fanmoves andstops. •
Harness andconnector
"OFF", or"LOW" and"HI" •
Cooling fanmotor
and "OFF" usingCONSULT .
• Ignition switch:ON(Engine
FUEL PUMP stopped)
Fuelpump relaymakes theoper- •Harness andconnector
• Turn thefuel pump relay"ON"
RELAY and"OFF" usingCONSULT ating
sound. •
Fuel pump relay
and listen tooperating sound.
EGRC SOLENOID
VALVE (EVAP canister
•Ignition switch:ON
purge control
•Turn solenoid valve"ON" and Solenoid
valvemakes anoperat- •
Harness andconnector
solenoid valveor
EGR valve
&
"OFF"
withtheCONSULT andingsound. •
Solenoid valve
EVAP canister listen
tooperating sound.
purge control
solenoid valve)
•Ignition switch:ON
VALVE TIMING •
Turn solenoid valve"ON" and Solenoid
valvemakes anoperat- •
Harness andconnector
SOL*2 "OFF"
usingCONSULT anding
sound. •
Solenoid valve
listen tooperating sound.
SELF-LEARNING •
Inthis test, thecoefficient ofself-learning controlmixture ratioreturns tothe original coefficient by
CONT touching
"CLEAR" onthe screen.
*1: Heated oxygen sensor(ForEurope andIsrael, andAustralia A/Tmodels)
Oxygen sensor(Except forEurope andIsrael, andAustralia A/Tmodels)
*2: GA16DE except forEurope andIsrael
*3: GA16DE engine A/Tmodels forEurope without heavydutykithave a2- step control [ON/OFF] system."LOW"and"HI"
are shown onCONSULT screentorepresent "ON"condition.
EC-53
•

ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION
CONSULT (Conl'd)
FUNCTION TEST
CONDITION JUDGEMENT
ITEM CHECK
ITEM(REMEDY)
• Ignition switch:ON
COOLING FAN (Engine
stopped)
Thecooling fanrotates andstops every •
Harness andconnector
CIRCUIT •
Cooling fancircuit is
3seconds. •
Cooling fanmotor
tested whencooling fanis
•Cooling fanrelay
rotated .
• Ignition switch:ON-.
START
• Start signal circuit is
tested whenengine is
started byoperating the
starter. Beforecranking,
START SIGNAL batteryvoltage andengine
Startsignal: OFF-.ON •
Harness andconnector
CIRCUIT coolanttemperature are •
Ignition switch
displayed. During
cranking, averagebattery
voltage, massairflow
sensor outputvoltage and
cranking speedaredis-
played .
• Ignition switch:ON
(Engine running)
Lockedposition ON
•Harness andconnector
PW/ST SIGNAL •
Power steering circuitis
•Power steering oilpres-
tested whensteering
CIRCUIT wheelisrotated fullyand sure
switch
then settoastraight lineNeutral
position OFF•
Power steering pump
running position.
• Vehicle speedsensor cir-
•Harness andconnector
VEHICLE SPEED cuit
istested whenvehicle Vehicle
speedsensor inputsignal is
•Vehicle speedsensor
SEN CKT is
running ataspeed of10 greater
than4km/h (2MPH)
•Electric speedometer
km/h (6MPH) orhigher .
• After warming up,idle the
engine. •Adjust ignition timing(by
• Ignition timingadjustment
movingcamshaft position
IGN TIMING ADJ is
checked byreading The
timing lightindicates thesame
sensorordistributor)
ignition timingwithatim- value
onthe screen.
•Camshaft positionsensor
ing light andchecking
drivemechanism
whether itagrees with
specifications.
•INJECTION SYS(Injector,
fuel pressure regulator,
harness orconnector)
• Air-fuel ratiofeedback cir- •
IGNITION SYS(Spark
cuit (injection system,igni- plug,
power transistor,
tion system, vacuum ignition
coil,harness or
MIXTURE RATIO system,
etc.)istested byOxygen
sensor'1 COUNT:Morethan5 connector)
TEST examining
theoxygen times
during 10seconds •
VACUUM SYS(Intake air
sensor'1 outputat2,000 leaks)
rpm under non-loaded •
Oxygen sensor'1 circuit
state. •
Oxygen sensor'1 opera-
tion
• Fuel pressure highorlow
• Mass airflow sensor
'1: Heated oxygen sensor(ForEurope andIsrael, andAustralia AITmodels)
Oxygen sensor(Except forEurope andIsrael, andAustralia
A/T
models)
EC-55
•

TROUBLEDIAGNOSES -General Description
Symptom MatrixChart(Cont'd)
SYMPTOM
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AA ASAC AD AEAFAG AH AJAK ALAM HA
ECCS Camshaft
positionsensorcircuit
•••
0
0
()
0 0
EC-94
Mass airflow sensor circuit
••
•
0
•
••
•
EC-101
(Heated) oxygensensorcircuit
••
0
• •
•
•
EC-189,194
Engine coolant temperature sensor
••
•
0
••
•
•
•
•
EC-108
circuit
Throttle position sensorcircuit
•• ••• ••
•
EC-128
Incorrect throttleposition sensor
•
()
()
•
0
0
•
()
EC-65
adjustment
Vehicle speedsensor circuit
0
C)
()
0
EC-133
Knock sensor circuit
000 0
EC-119
ECM
0
()
0 0
()
0
()
()()
0 0
EC-64
Start signal circuit
0
EC-138
Park/Neutral positionswitchcircuit
0
0
0
0
0
EC-173
Power steering oilpressure switchcir-
0
(J
0
EC-169
cuit
• ;High Possibility Item
0;
Low Possibility Item
EC-72
(continued
onnext page)

TROUBLEDIAGNOSIS FORNON-DETECTABLE ITEMS
SYSTEM DESCRIPTION Idle
AirControl Valve(IACV) -Auxiliary Air
Control (AAC)Valve
Camshaft positionsensor Engine
speed
I
Mass
airflow sensor Amount
ofintake air
I
Engine coolant temperature sensor Engine
coolant temperature
~
I
Ignition switch Start
signal
I
Throttle positionsensor Throttle
position
~
I
Inhibitor switch(A/Tmodels)/
Park/Neutralposition
Neutral position switch(M/Tmodels) ECM
(ECCS
Air conditioner operation control
!
IACV-AAC valve
I
Air conditioner switch
module)
Power steering oilpressure switch Power
steering loadsignal
I
Battery
~
Battery voltage
Vehicle speedsensor Vehicle
speed
Cooling fanrelay Cooling
fanoperation
Load switch' Electrical
load
Blower fanswitch Blower
fanoperation
': Rear window defogger switchandheadlamp switch.
This system automatically controlsengineidlespeed toaspecified level.Idlespeed iscontrolled
through fineadjustment ofthe amount ofair which bypasses thethrottle valveviaIACV-AAC valve.The
IACV-AAC valveopens andcloses (except forEurope andIsrael), orrepeats ON/OFF operation (for
Europe andIsrael), according tothe signal sentfrom theECM. Thecamshaft positionsensordetects
the actual engine speedandsends asignal tothe ECM. TheECM thencontrols theIACV-AAC valveso
that engine speedcoincides withthetarget valuememorized inECM. Thetarget engine speedisthe
lowest speedatwhich theengine canoperate steadily. Theoptimum valuestored inthe ECM isdeter-
mined bytaking intoconsideration variousengineconditions, suchasduring warmup,deceleration, and
engine load(airconditioner, powersteering andcooling fanoperation).
COMPONENT DESCRIPTION
IACV-AAC valve-Except forEurope andIsrael
The IACV-AAC valveismoved byopen andclose signals from
the ECM. When theopen signal issent tothe valve, theamount
of air that willflow through thevalve increases. Themore air
that flows through thevalve, thehigher theidle speed. When
the close signal issent tothe valve. theamount ofair
decreases.
EC-150

TROUBLEDIAGNOSIS FORNON-DETECTABLE ITEMS
EVAP Canister PurgeControl Solenoid Valve
GA16DE MITmodels exceptforEurope, Israeland
Australia
SYSTEM DESCRIPTION
Camshaft positionsensor
Engine coolant temperature sensor
Mass airflow sensor
Throttle positionsensor
Ignition switch
Vehicle speedsensor Engine
speed
Engine coolant temperature
Amount ofintake air
Throttle position
Start signal
Vehicle speed ECM
(ECCS
control
module) EVAP
canister
purge control
solenoid valve
•
This system cutsandcontrols theport vacuum
applied tothe EVAP canister purgecontrol sole-
noid valve tosuit engine operating conditions.
This cut-and-control operationisaccomplished
through theECM. When theECM detects anyof
the following conditions, currentflowsthrough
the solenoid valveinthe EVAP canister purge
control solenoid valvecontrol vacuum line. This
causes theport vacuum tobe discharged
into theatmosphere sothat theEVAP canister
purge lineremains closed.
• Engine starting
• Closed throttle position
• Low andhigh engine coolant temperature
• During deceleration
• Engine stopped
• Vehicle speed:below10km/h (6MPH)
• Mass airflow sensor malfunction
W>
Vacuum
signal
SEF240PG COMPONENT
DESCRIPTION
The EVAP canister purgecontrol solenoid valveresponds to
signals fromtheECM. When theECM sends anON (ground)
signal, thecoil inthe solenoid valveisenergized. Aplunger will
then move tocut the vacuum signal(fromtheintake manifc,ld
to the EVAP canister purgecontrol solenoid valve).
When theECM sends anOFF signal, thevacuum signalpasses
through thesolenoid valve.Thesignal thenreaches theEVAP
canister purgecontrol solenoid valve.
EC-179

TROUBLEDIAGNOSIS FORNON-DETECTABLE ITEMS
EGR Valve andEVAP Canister PurgeControl
Solenoid Valve
For Europe, IsraelandAustralia, andGA15DE MIT
models
SYSTEM DESCRIPTION
Camshaft positionsensor
Engine coolant temperature sensor
Mass airflow sensor
Throttle position sensor
Ignition switch
Vehicle speedsensor Engine
speed
Engine coolant temperature
Amount ofintake air
Throttle position
Start signal
Vehicle speed ECM
(ECCS
control module) EGR
valve
&
EVAP canister
purge control
solenoid valve
•
This system cutsandcontrols theport vacuum
applied tothe EGR valve andEVAP canister
purge control solenoid valvetosuit engine oper-
ating conditions.
This cut-and-control operationisaccomplished
through theECM. When theECM detects anyof
the following conditions, currentflowsthrough
the solenoid valveinthe EGR valve andEVAP
canister purgecontrol solenoid valvecontrol vac-
uum line. This
causes theport vacuum tobe discharged
into theatmosphere sothat theEGR valve and
EVAP canister purgelineremains closed.
• Engine starting
• Closed throttle position
• Low andhigh engine coolant temperature
• During deceleration
• Engine stopped
• Vehicle speed:below10km/h (6MPH)
• Mass airflow sensor malfunction
SEF783K
l#
Intake
manifold
vacuum signal
SEF240PF COMPONENT
DESCRIPTION
Exhaust gasrecirculation (EGR)valve
The EGR valve controls theamount ofexhaust gasrouted tothe
intake manifold. Vacuumisapplied tothe EGR valve in
response tothrottle valveopening. Thevacuum controls the
movement ofataper valve connected tothe vacuum diaphragm
in the EGR valve.
EGR valve andEVAP canister purgecontrol solenoid
valve
The EGR valve andEVAP canister purgecontrol solenoid valve
responds tosignals fromtheECM. When theECM sends anON
(ground) signal,thecoil inthe solenoid valveisenergized. A
plunger willthen move tocut the vacuum signal(fromthethrot-
tle body tothe EGR valve andEVAP canister purgevalve).
When theECM sends anOFF signal, thevacuum signalpasses
through thesolenoid valve.Thesignal thenreaches theEGR
valve andEVAP canister.
EC-183

TROUBLEDIAGNOSIS FORNON-DETECTABLE ITEMS
Valve Timing Control (VTC)
SYSTEM DESCRIPTION
Mass airflow sensor Amount
ofintake air
Camshaft positionsensor Enginespeed
Engine coolant temperature sensorEnginecoolant temperature ECM
(ECCS
control module) Valve
timing
control solenoid
valve
Throttle positionsensor Throttle
position
The valve timing control system isutilized toincrease engineperformance. Intakevalveopening and
closing timeiscontrolled, accordingtothe engine operating conditions, bythe ECM.
Engine coolant temperature signals,enginespeed,amount ofintake air,throttle position, vehiclespeed
and gear position areused todetermine intakevalvetiming.
The intake camshaft pulleyposition isregulated byoil pressure, whichiscontrolled bythe valve timing
control solenoid valve.
Drain .. Intake
airsignal (From massairflow sensor)
Engine speedsignal(From camshaft positionsensor)
Engine coolant temperature (Fromengine coolant temperature sensor)
Throttle valveidleposition (Fromthrottle position sensor)
Vehicle speed(Fromvehicle speedsensor)
"'- Camshaft (Intakeside)
EGM
(EGGS
control
module)
/
Camshaft sprocket
Piston
Valve
timing control ~
»
'o'""oid ,,',"
Ii
/
Return spring
MEF572DA
EC-198