MITSUBISHI GALANT 1989 Service Repair Manual
Manufacturer: MITSUBISHI, Model Year: 1989, Model line: GALANT, Model: MITSUBISHI GALANT 1989Pages: 1273, PDF Size: 37.62 MB
Page 211 of 1273

FUEL SYSTEM
of MFI Components13-69
CAMSHAFT POSITION SENSOR
\ /‘4 iI ‘j6FUO857
r
1
Out put characteristic ‘“!I
pm
One rotation of distributorOlR0102
Ignition switch (IG,) ~~~!%k?nt
side ,Distributor4 3
Camshaft position
sensor
Distributor
connector 5EL1401
@ Harness sideconnectorT
Engine control moduleA22
V
L
6FU1255
OPERATION
l The camshaft position sensor functions to de-
tect the top dead center position of the No. 1cylinder and to convert those data to pulse sig-
nals that are input to the engine control module.
The engine control module, based upon those
signals, calculates the sequence of fuel injec-
tion.
TROUBLESHOOTING HINTS
If there is a malfunction of the camshaft position
sensor, the sequential injection will not be correct, l
The power for the camshaft position sensor is
supplied from the ignition
switch-IG and is
grounded to the vehicle body. The camshaft
position sensor, by intermitting the flow (to
ground) of the
5V voltage applied from the en-
gine control module, produces pulse signals.
resulting in such problems as engine stalling, un-
stable idling, and poor acceleration.
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Page 212 of 1273

‘13-70 FUEL SYSTEM
(1) Run the engine at the idle speed.
(2) Connect the
probe to the oscilloscope pick-up point in the 5v
-- circuit diagram, and check the
waveform.
ov -
Normal waveform
6FU1395
HARNESS INSPECTION
IJ
Har
con
@
Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
switch)ZJ
Harness sideconnector
--
[a
/T
Y
gp
TT
,
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Check for continuity of the ground
circuit.
. Connector: Disconnected
Repair the
harness.
@El-Ground)
Check the voltage of the output cir-
cuit.
. Connector: Disconnected
. Ignition switch: ON
Page 213 of 1273

FUEL SYSTEM
CAMSHAFT POSITION SENSOR
sensor/
WV?: (I 6FUO857
Out put charactenstic
I->Time
One rotatton of distributor01 R0102
@ Component side
connector
Ignition switch (IG,)
I
\/\/\/\/\/\/4 2
&T]
f-b
9r
Engine control moduleA 22
h
5v
OPERATION
TROUBLESHOOTING HINTS
INSPECTION-Using Oscilloscope
Refer to P.13-69.
HARNESS INSPECTION
Harness side
connector
@
7FUO49t
r1 TSB Revision Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
Voltage
(V)
Battery positive voltage
Iswitch)
Page 214 of 1273

13-72 FUEL SYSTEM
2Harness stdeCheck for continuity of the ground
circuit.
Connector: Disconnected
Repair the
harness.
* Fzml-Ground)
7FUO497
. Connector: Disconnected
. Ignition switch: ON
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Page 215 of 1273

FUEL SYSTEM
inspection of MFI Components13-73
CRANKSHAFT POSITION SENSOR
\IDikZ!utoJP
[VI 1 Out put characteristic
One rotation of distributor Ignition switch
(IG,)
@ Component sideconnector
Distributor3
Distributor
connector
@ Harness sideconnector
/ CraTSiti0 y$/
A21 Engine control module
LD5vLI
6Fu1256
OPERATION
l The crankshaft position sensor functions to de-
tect the crank angle (position) of each cylinder,
and to convert those data to pulse signals,
which are then input to the engine control mod-
ule. The engine control module, based upon
those signals, calculates the engine rpm, and
also regulates the fuel injection timing and the
ignition timing.
TROUBLESHOOTING HINTS
Hint 1:If an impact is suddenly felt during driving or the en-
gine suddenly stalls during idling, try shaking the
crankshaft position sensor during idling. If the engine stalls, the cause may be presumed to
be improper or incomplete contact of the crank-
shaft position sensor’s connector. Hint 2:If the crankshaft position sensor output rpm is 0
rpm during cranking when the engine cannot be
started, the cause may be presumed to be a
mal-
l The power for the crankshaft position sensor is
supplied from the ignition
switch-IG and is
grounded to the vehicle body. The crankshaft position sensor, by intermitting the flow (to
ground) of the
5V voltage applied from the en-
gine control module, produces pulse signals.
function of the crankshaft position sensor or a bro- ken timing belt.
Hint 3:
If the indicated value of the crankshaft position sen-
sor output rpm is 0 rpm during cranking when the
engine cannot be started, the cause may be pre-
sumed to be a failure of the ignition coil’s primary current to intermittently pulse correctly, so a mal-
function of the ignition system circuitry, the ignition
coil and/or the ignition power transistor is the prob-
able cause.
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Page 216 of 1273

13-74 FUEL SYSTEM
Hint 4:
If idling is possible even though the crankshaft posi-
tion sensor indicated rpm is a deviation from the standard value, the cause is usually a malfunction of
something other than the crankshaft position sen-
sor.
Examples:
(1) Malfunction of the coolant-temperature sensor.
(2) Malfunction of the idling-speed control motor.
(3) Improper adjustment of the standard idling
speed.
INSPECTION
Using Scan tool
FunctionItem No.
Data reading 22 Data display
Inspection conditions DescriptionNormal condition
Cranking rpm . Engine: Cranking Compare crankingBoth agree.
. Tachometer connection rpm and scan tool
(Check intermittent flow of indicated
rpm._ignition coil primary current
by tachometer.)
Function
Data reading Item No.22
Data display1 Inspection conditions 1 Engine coolant temperature 1 Standard value1
1 At 40°C (104°F)1 900-1,100rpm 1
III-I( At 80°C (176°F)1 150-850 rpm
Normal waveform
03AO202
HARNESS INSPECTION
Ilr I
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.
Harness side
connector
@
Measure the power SUPPIY voltaoe.
. Connector: Disconnected
-. Ignition switch: ON
1 TSB Revision
Page 217 of 1273

FUEL SYSTEM
@ Harness srdeconnector
@ Harness sideconnector
Check for continuity of the ground
circuit.
. Connector: Disconnected
1 Reoair the
t
hainess.
(@B-Ground)
Check the voltage of the output cir-
cuit.
. Connector: Disconnected
. ignition switch: ON
u
O
K
ASTOP
Repair the
harness.
(@m-m)
CRANKSHAFT POSITION SENSOR
m/i /i 6FUO6571
[VI 1 Output characteristic
@ Component sideconnector
Ignition switch (IG1)
One rotation of crankshaftposition sensor
01R0’05
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Engine control module,( 21
m---l 7F”04pp
I
Page 218 of 1273

13-76 FUEL SYSTEM
OPERATION
TROUBLESHOOTING HINTS
INSPECTION-Using Scan toolINSPECTION-Using Oscilloscope
Refer to P.13-73.
HARNESS INSPECTION
7
7FlJO49t
@Harness sideconnector
7FUO497
ISS stde connector
Measure the power supply voltage.
. Connector: Disconnected
. Ignition
switch: ON
Voltage (VI
Battery positive voltageI
cl2
Repair theharness.
K%l-Ignition
switch)
Check for continuity of the ground
circuit,
Connector: Disconnected
Repair the
harness.
@RI-Ground)
Check the voltage of the output cir-
cuit.
. Connector: Disconnected
. Ignition switch: ON
0
O
K
a@
Repair theharness.
vi!iaI-m1,
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Page 219 of 1273

FUEL SYSTEM
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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Page 220 of 1273
