check engine MITSUBISHI GALANT 1989 Service Manual Online

IS-64 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
IDLE SPEED CONTROL MOTOR POSITION SENSOR
MIOWAD
@ Component sideIdle speed control motor
connectorposition sensor
l-F---

-
@ Harness side I--
connector
i5EL1402,
4,0
t t
13 A23A17 A14 A24
Enginecontrol
module
: 5v 5v
lFUO514
Fnnirw rnntrol
module connector
Plunger stroke
OlROlOlOlL0838
OPERATION
l The idle speed control motor position sensor functions to convert the data concerning theposition of the plunger (located within the idle-
speed control motor) to voltage, and to input
that voltage (as signals) to the engine control
module. The engine control module, based upon
those signals, then functions to regulate the idle-speed control motor.
l The
5V power supply within the engine control
module is supplied to the idle speed control
position sensor; it then passes through the re-
sistance within the sensor and is grounded at
the engine control module.
TROUBLESHOOTING HINTS
Hint 1’
The idle speed control motor position sensor is the
most important sensor for control of the idling
speed; there is very often a malfunction of this sen-
sor if a problem occurs when the ,engine load is
caused to fluctuate, such as when, during idling, the
air conditioning switch is switched back and forth
between OFF and ON, etc. l
When the plunger located within the idle-speed
control motor extends from its contracted con-
dition, the resistance between the idle speed
control motor position sensor’s variable-resist-
ance terminal and the ground terminal also in-
creases in accordance with that extension. As a
result, the voltage of the idle speed control
motor position sensor’s variable-resistance ter-
minal also becomes higher in accordance with
the extension.
Hint 2:
If the output voltage of the idle speed control motor
position sensor deviates from the standard value
even though the results of the checking of the idle
speed control motor position sensor harness and of
the component itself are normal, the malfunction
may be presumed to be among the following:
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13-66 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
Harness
sde
connectorI
OlAO362
@ Harness sideconnector
Engine control
module harnessside connector
I-
r
MD9984646FUO666
MD9984646FUo666
A
Check for continuity of the groundcircuit.
. Connector: Disconnected
t
Repair theharness.

l&l)
Check for an open-circuit, or a short-circuit to ground between the engine
control module and the idle speed
control motor position sensor.
* Engine control module connector:f-
A
1
Disconnected
. idle speed control motor position sensor connector: Disconnected Repair the
harness.
~@[z1-8)
I
SENSOR INSPECTION
Disconnect the idle speed control motor position sensor
connector, and connect the special tool (test harness) to
the connector on idle speed control motor position sensor side.
Measure the resistance between terminal
@ (black clip of
special tool) and terminal
0 (white clip) of the idle speed
control motor position sensor connector.
Standard value: 4-6
kS2
(3) Disconnect the idle speed control motor connector.
(4) Connect a
6V DC power supply between terminals 0 and
@ of the idle speed control motor connector to activate
(extend and retract) the idle speed control motor. Measure
the resistance between terminal
@ (black clip of special
tool) and terminal
0 (red clip) of the idle speed control
motor position sensor connector.
Standard value: Smooth increase/decrease in ac-
cordance with extension and retrac-
tion of 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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.-•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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‘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

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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FUEL SYSTEM VALVE> -On-Vehicule lnsoection of MFI Comoonents13975
@ 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 MIBYMAB
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

13-78 FUEL SYSTEM VALVE> -On-Vehicule inspection of MFI Components
IGNITION SWITCH-ST AND PARK/NEUTRAL POSITION SWITCH
MI3YOAa
Park/neutral position s( I‘\\ \
1lclnition switch (ST)
Componentside connector@
108
Engine ’control
module
Harness side@I connectorI7
Engine control module connector
OlLO838
OPERATION
lThe ignition switch-ST inputs HIGH-level signals
to the engine control module during engine cranking. The engine control module, based on
those signals, regulates fuel injection during
starting, etc.
l When the ignition switch is set to START, the
battery voltage during engine cranking is, by
way of the ignition switch and the park/neutral
position switch, applied to the engine control
module, and the engine control module thus de-
tects the fact that the engine is cranking.
Note that battery voltage is not applied to the
engine control module if the position of the se- lector lever is other than the “P” or “N” range.
l The park/neutral position switch functions to convert the voltage to HIGH level or LOW level
TROUBLESHOOTING HINTS
If the output of the park/neutral position switch is
abnormal even though the results of the checking
of the park/neutral position switch harness and of depending upon whether the selector lever is at
the “P” or “N” range or is at some position other
than the “P” or “N” range, and inputs the result
to the engine control module. The engine con-
trol module, based upon those signals, then reg-
ulates the operation of the idle speed control
motor.
l Battery voltage within the engine control mod-
ule is applied, by way of the resistance, to the
park/neutral position switch. When the selector
lever is set to the
‘7” or “N” range, continuity is
created, via the starter motor, between the en-
gine control module’s park/neutral position
switch terminal and ground, and the terminal
voltage becomes LOW level.
the component itself are normal, it is probable that
the cause is improper adjustment of the control
cable.
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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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13-80 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
VEHICLE SPEED SENSOR
Vehicle speed sensor
Vehicle speed sensor
IV1
-errnInafoltage
102418
Frwyy 1/
Component side@ connector
Component side@ connector
6FU1410
Engine control
module
5v
MIBVPAA
Vehicle speed sensor
Engine control module connector Vetwle
speed [km/h (mph)]
16245

1
OlLO838
OPERATION
l
The vehicle-speed sensor is incorporated within
the speedometer; it converts vehicle-speed
data to pulse signals and inputs those signals to
the engine control module. The engine control
module, based upon those signals, regulates the
idle-speed control motor, etc.
TROUBLESHOOTING HINTS l
The vehicle-speed sensor, by intermitting by the
reed switch the flow (to ground) of the approxi-
mately
5V voltage applied from the engine con-
trol
module, produces vehicle-speed signals.
If ‘there is damaged or disconnected wiring, or a
short-circuit, of the vehicle-speed sensor signal
circuit. the engine may stall when the vehicle speed is reduced and the vehicle is stopped.
HARNESS INSPECTION
-side connector
_--- _
ia
_, - .,
:_--
gp
p
L
11Engine control
module harness
=l01AOW(1
I
Check the vehicle speed sensor out-
put circuit for continuity.
. Engine control module connector: Disconnected
. Move the vehicle.
) TSBRevision