display MITSUBISHI GALANT 1989 Service User Guide

FUEL SYSTEM -On-Vehicule Inspection of MFI CmpOnentS13977
IGNITION SWITCH-ST
>
Engine control module connector
II
Enginecontrolmodule01 LO838
Ignition switch (ST)
7
Tr108104
T-7JL
6FU1257
OPERATION
lThe ignition switch-ST inputs HIGH-level signalslWhen the ignition switch is set to START, the
to the engine control module during engine battery voltage during engine cranking is, by
cranking. The engine control module, based onway of the ignition switch, applied to the engine
those signals, regulates fuel injection during
control module, and the engine control module
starting, etc.thus detects the fact that the engine is cranking.
INSPECTION
Using Scan tool
Function Item No.1 Data display
Inspection conditions EngineNormal indication
Data reading 18 Switch status
Ignition switch: ON
Stopping
OFF
CrankingON
HARNESS INSPECTlON
Engine controlmodule harness
side connector
Measure the input voltage to the en-
gine control module.
. Engine control module connector: Disconnected
- Ignition switch: START
r6FU1259i
Repair theharness. @El-
Ground)
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FUEL SYSTEM - On-Vehicule Inspection of MFI Components13-79
INSPECTION
Using Scan tool
Ignition switch-ST
Function Item No.Data display Check conditions
EngineNormal display
Data reading 18 Switch status
. Ignition switch: ON Stopped
OFF
CrankingON
Park/neutral position switch
Function
Item No.Data display
Check conditions Selector lever position
Normal display
Data reading 29 Shift position
. Ignition

swatch: ON Por NPor N
D, 2, Lor RD, 2, L or R
HARNESS INSPECTION
Harness sideconnector
Engine control
Measure the input voltage of engine
control module.
. Engine control module connector: Disconnected
. Park/neutral position switch con-
nector: Connected
* Selector lever: “P” range
. Ignition switch: START
Voltage (V)
:
1
Y-OlLO42’f
PARK/NEUTRAL POSITION SWITCH INSPECTION
Measure the power supply voltage of
the park/neutral position switch.
. Engine control module connector: Disconnected
. Park/neutral position switch con-
nector: Disconnected
Check the
I+
power
supply cir-
cuit.
Measure the park/neutral position
switch terminal input voltage.
* Engine control module connector: ConnectedPark/neutral position switch con-
nector: Disconnected
8 or more
ASTOP
Repair the
harness.
C@W lIEI)
Refer to GROUP 23-Troubleshooting.
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13-82 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
OPERATION
l The power-steering pressure switch functions
to convert data as to whether there is or is not apower steering load to LOW-or HIGH-level vol-
tage, and the resulting signals are input to the engine control module. The engine control mod-
ule, based upon those signals, regulates the
idle-speed control motor. l The battery voltage within the engine control
module is applied, by way of the resistance, to
the power-steering pressure switch. When
steering maneuvers are made, the pressure of
the power-steering oil increases, thus switching
ON the power-steering pressure switch, with
the result that the current is grounded. As a re-
sult, the power-steering pressure switch vol-
tage changes from HIGH level to LOW level.
INSPECTION I) Using Scan tool
Function
Item No.
Data reading 27
Data displayInspection conditions Steering wheelNormal indication
Switch status Engine: IdlingSteering wheel idle stateOFF
During steering wheelONoperation
(2) Checking Oil Pressure
Steering wheel
Straight forward
Turned
Oil pump delivery pressure (ref. value)
less than 1,470- 1,961 kPa (213-284 psi)
more than
1,470- 1,961 kPa (213-284 psi)
HARNESS INSPECTION
I-E-I
Harness side connector 6 0
@=- -0
Q
4 1
Measure the power supply voltage.
. Connector: Disconnected. Ignition switch: ON
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13-84 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
INSPECTION
Using Scan tool
Air conditioning switch
Function Item
No.
Data reading 28 Data display
Check conditions Air conditioning switch
Normal display
Switch status . Engine idling (The air
OFF OFFconditioning com-
pressor should be ac-ON ONtivated when the air
conditioning switch is
switched ON.)
Air conditioning compressor clutch relay
Function
Data reading Item
No. Data display
49Air condition-
ing compres-
sor clutch relay status Check conditions
. Engine: idling after
warm up
HARNESS INSPECTION
Air conditioning switch Normal display
OFFOFF (Compressor
clutch non-activation)
ON ON(Compressor
clutch activation)
,--=+aI_I Engine controlmodule harnessside connector
OlROB13
Measure the power supply voltage of
the air conditioning circuit.
. Engine control module connector: Disconnected
. ignition switch: ON
* Air conditioning switch: ON4
ASTOP
Check the
air condi-
tioning cir-
cuit.
AIR CONDITIONING INSPECTION Refet to GROUP
55-Air conditioning.
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13-86 FUEL SYSTEM - On-Vehicule inspection of MFI Components
Using Scan tool
FunctionItem No.Data display Inspection conditions Engine condition
Standard value
Data reading 43 Sensor. Engine: warm up
750 rpm (Idling)
70°C or lower
temperature . Engine is maintained in a
constant state for 2 minutes 3,500 rpm
70°C or higher
or more
. Remove the vacuum hose
(green stripes) from the EGR
solenoid and plug both the removed vacuum hose end
and solenoid valve nipple.
HARNESS INSPECTION
Harness sideconnector
@qqJ
I
II
EL -:
f7
Q,
L *A’
-1I01.0523
Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
Harness sideconnector
Check for continuity of the ground
circuit.
. Connector: Disconnected
SENSOR INSPECTION
Refer to GROUP 17-Exhaust Gas Recirculation (EGR)
System.
-w
STOP
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13-88 FUEL SYSTEM VALVE>- On-Vehicule Inspection of MFI Components
TROUBLESHOOTING HINTS
Hint I’
The exhaust gas purification performance will
Examples:
(1) Malfunction of an injector.
worsen if there is a malfunction of the oxygen sensor. Hint 2:
If the oxygen sensor output voltage deviates from
the standard value even though the results of the
checking of the oxygen sensor are normal, the
cause is probably a malfunction of a component related to mixture control. (2) Air leakage into the intake manifold from a
leaking gasket.
(3) Malfunction of the volume air flow sensor, the intake air temperature sensor, the barometric-
pressure sensor, or the engine coolant tempera-
ture sensor.
Data reading
INSPECTION
Using Scan tool
HARNESS INSPECTION
Data display
Sensor de-
tection vol-
tage Inspection conditions
Engine conditionStandard value
Engine: warm up When sudden decel-
250
mV or lower
(Make the mixture lean eration from 4,000 rpm
by engine speed reduc-
tion, and rich by racing) When engine is sud-
500- 1,000 mV
denly raced
Engine: warm up750 rpm (Idling)
(using the oxygen sen-
sor sianal.
check the air/
400
mV or lower
I I
(changes)
fuel mixture ratio, and600-l ,000 mValso check the condition 2,000 rpm
of control by the engine
control module)
I CALIF@I Hal
FEDHarness
ness
side
connector
Engine control
module harness
side connector
Check for an open-circuit, or a short-circuit to ground between the engine
control module and the oxwen sen-f7 _-
~~SOT.‘-. r$;rdn sensor connector: Drscon-
. Engine control module connector:Disconnected CALIF
Harness side
Check for continuity of the ground
.“‘..“...;;”
Repair theharness.
KEEI-Ground)
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FUEL SYSTEM -On-Vehicule
Inspection of MFI Components13-91
INSPECTION
Using Scan tool
FunctionItem No. Data display
Data reading 41
III~~~ion
Inspection conditions Engine coolant temperature Standard value
Engine cranking At
0°C (3~2°F)“~Approx. 21 ms
At
20°C (68°F)Approx. 43 ms
At
80°C (176°F)Approx. 10 ms
FunctionItem No.
Data reading 41
L
Data display
Ac&a$ion
Inspection conditions
. Engine coolant tempera- ture:
85-95°C (185-205°F)* Lights, cooling fan, electric-al accessories: OFF
. Transaxle: neutral
(A/T models: “P” range) Engine condition
Standard value
I
750 rpm (Idling)2.5-4.0 ms
I
NOTE*I: The injector activation time indicates the time under the following con\
ditions: a power source voltage of 11V and a
cranking rpm of 250 rpm or less.
**: Simultaneous injection at four cylinders when engine coolant temperatur\
e is 0°C (32°F).*3: The injector activation time may be about 10% longer than indicated abo\
ve when the vehicle is new [driven approximately 500 km (300 miles) or less].
FunctionItem No.
Actuator test
01
02
03
04
Description
No.
1 injector is shut off.
No. 2 injector is shut off.
No. 3 injector is shut off.
No. 4 injector is shut off. Inspection conditions
Normal indication
Engine: idling after warm The idling condition
changes more.
r”sput off the injectors in(Either becomes more un-sequence during after stable, or engine stalls.)
engine warm-up, check
the idling condition.)
-
I i-. --.-~-db$- A: Injector~__
Normal waveformdrrve time
HARNESS INSPECTION
1
P
Using Oscilloscope
(1) Run the engine at idle speed.
(2) Connect the probe to the oscilloscope pick-up point as
shown in the circuit diagram, and check the waveform at
the drive side of each injector.
Measure the power supply voltage of
the injector.
. Connector: Disconnected. Ignition switch: ON
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13-96 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
IGNITION COIL AND IGNITION POWER TRANSISTOR
ignition coil (IGI)
Ml3WAA
Harness side
@connector0
Harness side
Component side
Distributor\/ 2
4.I_lgnltion. .!
I@LZ)
TachcImetertimingA? I--:*:^^adjustment-_
Lllrnacr
r;rlnI 101 i IG.72 Jl”F
Componenr side
6FU1280
OPERATION
l When the ignition power transistor unit is
switched ON by the signals from the engine
control module, the primary current of the igni-
tion coil will flow. When the ignition power tran-
sistor unit is switched OFF, the primary current
flow is interrupted, and high voltage is produced
at the secondary coil.
l When the engine control module switches OFF
INSPECTION
the power transistor within the unit, the battery
voltage within the unit is applied to the ignition
power transistor unit, and the ignition power
transistor unit is switched ON. In addition, the power transistor unit is switched OFF when the
engine control module switches ON the power
transistor within the unit.
Using Scan tool
1 Function1 Item No.1 Data display / Inspection conditions/ Engine condition 1 Standard value
Data reading 44
Ignition
advance . Engine: warm up
750 rpm (idling)5- 15 “BTDC. Timing light: set(Use the timing light to
check the actual ignition
2,000 rpm 30-40 “BTDCtiming.)
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Check item (Remedy)
l EGR valve control vacuumFUEL SYSTEM - Troubleshooting13423
NOTE1.Replace the engine control module if a diagnostic trouble code is output\
although the inspection reveals that there
is no problem with the check items.
2.The code numbers will be displayed in order, starting from the lowest.
TROUBLESHOOTING TABLE
NOTE *:
The failsafe/back-up function is in operation.
DE;;;zic On-board
diagnostic
code No. item Diagnostic content
Major causeRemarks (trouble
phenomenon, etc.)
EngineThe engine control module--l Engine stop
control itself is abnormal. l Impossible start
module
11Oxygen
sensor Though the air/fuel mixture
(1) The oxygen sensor is troubled.
l Deterioration of
ratio closed loop control is (2) Open-circuit, short-circuit or exhaust gas
operated, the signal voltage of improper connector contact purifying
the oxygen sensor does not occurs in the oxygen sensor performance*
vary (to be lean/rich). circuit.
(3) The fuel pressure is improper. l Deterioration of
(4) The injector is troubled. exhaust gas
(5) Air is sucked through the purifying
gasket clearance, etc. performance*
(6) The engine control module is l Abnormal start
troubled. l Unstable idling
l Abnormal
acceleration
12Volume
air flow
sensor Though the engine is running,
(1) Volume air flow sensor is l Abnormal
the signal frequency of the air troubled. acceleration*
flow sensor is 1
OHz or less. (2) Open-circuit, short-circuit or l Unstable idling*
improper connector contact
occurs in the volume air flow
sensor circuit.
(3) The engine control module is l Inappropriate idle
troubled. speed*
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On-Vehicle Inspection of MFI
13450FUEL SYSTEM VALVE> - Components
VOLUME AIR FLOW SENSOR
Intake air amountWsec)16245
1
@ Componentsideconnectof
Multiport
fuel
injection relay
/ohme air flow sensor/\2/\-
@Harness side
Isv xI 6FU1952
OPERATION TROUBLESHOOTING HINTSRefer to
P.13-49.
INSPECTION
Using Scan Tool
Item No.
12
Data displayInspection conditions Engine condition
Standard value
Sensor de- . Engine coolant Idle speed
18-44 Hz
tection airtemperature: 85-95°C
volume (fre- (185-205°F)
quency)
. Lights, cooling fan, elec-
2,000 rpm64-l 04 Hz tricaI
accessories: OFF
Transaxle: neutral
(PJTmodels: “P” range)RacingFrequency in-
creases as racing rpm increases.
NOTE
The volume air flow sensor output frequency may be about 10% higher than\
indicated above when the vehicle is new[driven approximately 500 km (300 miles) or less].
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