1989 MITSUBISHI GALANT Service Repair Manual

.-•r12-67FUEL SYSTEM -On-Vehicule Inspection of MFI Compontl=am - - =
IDLE SPEED CONTROL
MOTOR POSiTiON SENSOR
MlOWAE
@ Component sideconnectorIdle speed control mc)tor position sensor
‘{*q-r
T@ Harness sideLconnector
Voltagebetween
@n-@B
1.Plunger strokeI01R0101
I-@=%260jl
En$eecontrol
I3A23
’
A
L7A14 "2
4
I!-
Engine control module connector
6FU1246
01 LO838
OPERATION
TROUBLESHOOTING HINTS INSPECTION-Using Scan tool
Refer to P.13-64.
HARNESS INSPECTIONL
L-J1
@ Harness sideconnector
Measure the power supply voltage of
the idle speed control motor position
sensor.
* Connector: Disconnected- Ignition switch: ON
Check for continuity of the ground
circuit.
. Connector: Disconnected Repair the
harness.
@[zI El
-
m,
[231,
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Repair the
harness.
K&y-m*

13-68 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
Engine control
module harness
side connectorCheck for an open-circuit, or a short-circuit to ground, between the enginecontrol module and the idle speedcontrol motor position sensor.
. Engine control module connec-tor: Disconnected. Idle speed control motor positionsensor connector: Disconnected
0
O
K
1
ASTOP
i
Repair theharness.
KzEwDlfl,
!
Idle speed control motor
position sensor connector6FU1252
Idle speed control
motor connector
\A 6FU1253
-
SENSOR INSPECTION
(1) Disconnect the idle speed control motor position sensor
connector.
(2) Measure the resistance between terminals
@ and 0.
Standard value: 4-6 k&2
I) Disconnect the idle speed control motor connector.
.) Connect DC 6V between terminals @ and @ of the idle
speed control motor connector, and then measure the re-
sistance between terminals
@ and @ of the idle speed
control motor position sensor connector when the idle
speed control motor is activated (caused to expand and
contract).
Standard value: Smooth increase/decrease in ac-
cordance with expansion and con-
traction of the idle speed control
motor plunger.
Caution
Apply only a 6V DC or lower voltage. Application of
higher voltage could cause locking of the servo gears.
(5) If there is a deviation from the standard value, or if the change is not smooth, replace the idle speed control motor
assembly.
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FUEL SYSTEM - On-Vehicule lnwection
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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‘13-70 FUEL SYSTEM VALVE> -On-Vehicule inspection of MFI Components
(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

FUEL SYSTEM VALVE> -On-Vehicule Inspection of MFI Components13-71
CAMSHAFT POSITION SENSOR MlBYU8
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)

13-72 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
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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FUEL SYSTEM -On-Vehicule
inspection of MFI Components13-73
CRANKSHAFT POSITION SENSOR MllYMAA
\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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13-74 FUEL SYSTEM VALVE> -On-Vehicule inspection of MFI Components
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
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