1989 MITSUBISHI GALANT Service Repair Manual

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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13-124FUEL SYSTEM
- Troubleshooting
Diagnostic On-board
trouble diagnostic
code No.item Diagnostic content
Major causeRemarks (trouble
phenomenon, etc.)
13
14Intake air (1) The signal voltage of the (1) The intake air temperature
l Slightly impropertemperatu-intake air temperature
sensor is troubled.driveability*
re sensorsensor is 4.5V or higher.(2) Open-circuit, short-circuit or
l At high
(2) The signal voltage of the improper connector contacttemperatures,
intake air temperature occurs in the air intake (a) Improper start
sensor is
0.27V or lower. temperature sensor circuit.
(3) The engine control module isiWJ;sn$aple
troubled.
Throttle (1) The signal voltage of the (1) The throttle position sensor is
l Slightly improperposltion
throttle position sensor is troubled or improperly acceleration
sensor
0.2V or lower. adjusted. >
(2) Though the closed throttle (2) Open-circuit, short-circuit or l Improper
position switch is on, the improper connector contact
signal voltage of the occurs in the throttle position
d&eTbQ
throttle position sensor is
sensor circuit. l Engine stop2V or higher.
(3) The closed throttle position l Engine stop
switch ON is troubled.
(4) The closed throttle position l Racing is
switch signal line is impossible
short-circuited.
(5) The engine control module is
troubled.
21Engine(1) The signal voltage of the (1) The engine coolant
During cold weather
coolant engine coolant temperature sensor is troubled.
l Starting is
temperatu-temperature sensor is(2) Open-circuit, short-circuit or
impossible*.
re sensor4.6V or higher. improper connector contact l Unstable idling*
(2) The signal voltage of the occurs in the engine coolant
l Improper
engine coolant temperature sensor circuit. acceleration*
temperature sensor is (3) The engine control module is
0.11
V or lower. troubled.
(3) During engine warming-up, the engine
coolant temperature
sensor signal indicates
that the engine coolant
temperature drops.
22Crankshaft Though the engine is cranking (1) The crankshaft position sensor l Engine stop
position 4 seconds or more, the signal is troubled.0 Starting is
sensor voltage of the crankshaft (2) Open-circuit, short-circuit or impossible.
position sensor does not vary improper connector contact
(to be high/low). occurs in the crankshaft
position sensor circuit.
(3) The engine control module is
troubled.
23Camshaft Though the engine is running,(1) The camshaft position sensor is
l Unstable idling*
position the signal voltage of the
troubled.0 Improper
sensor camshaft position sensor does
(2) Open-circuit, short-circuit or acceleration*
not vary (to be high/low). improper connector contact
occurs in the camshaft position
sensor circuit.
(3) The engine control module is
troubled.
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FUEL SYSTEM - Troubleshootinn13-125
Dta,i;o;ic On-board
diagnostic
code No. item Diagnostic content
Major causeRemarks (trouble
phenomenon, etc.)
24
Vehicle
speed
sensor
(reed
switch) During acceleration of engine
(1) The vehicle speed sensor is The engine
revolution speed of 3,000 rpm troubled.sometimes cuts off
or more, the signal voltage of (2) Open-circuit, short-circuit or when stopping afte
the vehicle speed sensor does improper connector
contact
deceleration.
not vary (to be high/low). occurs in the vehicle speed
sensor circuit.
(3) The engine control module is troubled.
25Barometric (1) The signal voltage of the (1) The barometric pressure sensor l Unstable idling*
pressure barometric pressure is troubled. l Improper
sensor sensor is
4.5V or higher.(2) Open-circuit, short-circuit or acceleration*
(2) The signal voltage of the improper connector contact0 Improper start*
barometric pressure occurs in the barometric
sensor is
0.2V or lower. pressure sensor circuit.
(3) The engine control module is troubled.
36Ignition
timing
adjusting
signal The ignition timing adjusting
(1) The ignition timing adjusting
l Improper
signal line is short-circuited to signal line is short-circuited toacceleration
the ground. the ground.l Engine overheat
(2) The engine control module is troubled.
41Injector Injector is not continuously
driven for 4 seconds during
engine cranking or idle
operation. (1) The injector is troubled.
(2) Open-circuit, short-circuit or improper connector contact
occurs in the injector sensor
circuit. l Unstable idling
l Improper acceleration
0 improper start
(3) The engine control module is troubled.
43EGRDuring engine running after (1) The EGR valve is not opened. l Deterioration of exhaust gasnia>(1) The EGR amount is small.EGR valve control is excessively
purifying
(The signal voltage of the low. performance
EGR temperature sensor (3) The EGR solenoid is troubled.
is excessively high.) (4) The EGR temperature sensor is
(2) The signal voltage of the troubled.
EGR temperature sensor (5) Open-circuit, short-circuit or
is 0.1 V or less.improper connector contact
occurs in the EGR temperature
sensor circuit.
(6) The engine control module is
troubled.
55IAC valveIAC valve does not move to (1) The IAC valve position sensor is
position the intended position (opening troubled.l ;papp$Priate idle
sensor angle), even though idle air (2) Open-circuit, short-circuit or
l Engine stops*
control motor operates many improper connector contactl Unstable idling*
times. occurs in the
IAC valve position
sensor circuit.
(3) The idle air control motor (DC
motor) is troubled.
(4) Open-circuit, short-circuit or
improper connector contact
occurs in the idle air control
motor (DC motor) circuit.
(5) The engine control module is
troubled.
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13-126FUEL SYSTEM - Troubleshooting
FAILSAFE/BACK-UP FUNCTIONS LIST
If trouble with any major sensor is detected by the on-board diagnostic,\
the vehicle will be kept in the safe
driving conditions according to the preset control logic.
Trouble item Control content for trouble
Volume air flow(1)Fuel injection timing and ignition timing are determined according to th\
e throttle positionsensorsensor (TPS) and engine revolution speed signal (crankshaft position \
sensor signal).(2)The IAC motor is fixed in the appointed position so idle air control is not per\
formed.
Intake air temperature The control is executed with the suction air temperature regarded as
25°C (77°F).sensor
Throttle position The fuel injection rate is not increased for acceleration according to t\
he throttle position
sensor (TPS)sensor signal.
Engine coolantThe control is executed with the coolant temperature regarded as 80°C (176’F).temperature sensor
Camshaft positionSimultaneous injection of fuel is executed for all cylinders. (In this \
case, the
No.1 cylinder top
jenS0r
dead center is not detected at all after the ignition key is turned
on.)3arometric
pressure The control is executed with the pressure regarded as 760 mmHg
(30 in. Hg.).
sensor
AC valve position Idle air control motor is not performed.;ensor
Ixygen sensor
Closed loop control of the air/fuel mixture ratio is not executed.
READ OUT OF DIAGNOSTIC TROUBLE CODE
Refer to P.13-16.
EbW&R MEMORY OF DIAGNOSTIC TROUBLE
Refer to
P.13-17.
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FUEL SYSTEM VALVE> - Troubleshootins
CHECK CHART CLASSIFIED BY PROBLEM SYMPTOMS
ProblemsymptomsStartingIdling stability Drivingr”
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iP.13-143
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-
-Sheck items
‘ower
supply
%ginecontrol module power groundI
1 P.13-146
:uel pump
Jolume air flow sensor
B
f
E3
DELI @El
cP.13-162
P.13-165III P.13-167I
1/ P.l3-171 1
P.l3-172
P.l3-173
P.l3-175
P.13-176
P.l3-179
ntake air temperature sensor
BIB
DEI
0
DEl
3El
3
-I
iarometric
pressure sensor
ingine coolant temperature
sensor
‘hrottle position sensor
Iosed throttlepositionswitch
K valve oosition sensor
lamshaft position sensor
i-:rankshaft positionsensorIIlnition
switch-ST I
-I---0lnition switch-ST and park/neutralosition switch
chicle
speed sensor
ower steering pressure switch
ir conditioning switch and/C compressor clutch relayI/I- IIlxygen sensor
@El@ P.l3-181
@ElP.13-184
@[email protected]
Ile air control motor (DC motor)
inition coil and ignition powerOFI@piJOEIansistor
tiaporative emission purge solenoid01 P.13-189
1 Id
kl
c
tr
t
EGR solenoid @El@[email protected]
Fuel pressureOIlI @El8E.l @El @El @[email protected]
0 : Warm engine (number inside indicates check order)
0 : Cold engine (number inside indicates check order)
PROBLEM SYMPTOMS TABLE (FOR YOUR INFOMATION)
Refer to P.13-19.
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13-128FUEL SYSTEM - Troubleshooting
CIRCUIT DIAGRAM
< 1993 models>
IGNITIONSWITCH(ST)
I
SUB F'JILINK @
2
Licl
36
0
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FUEL SYSTEM - Troubleshooting13-129
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7
2F-BW
1
CONDENSERB-02-5
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----_-_--__
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AUTO COMPRESSORCONTROL UNIT
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6Ia 22
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ON:

235uPa
A-21
A-086,t
65m
1 TSB Revision1

13-130FUEL SYSTEM - Troubleshooting
CIRCUIT DIAGRAM (CONTINUED)
< 1993 models>
VOLUME
A-47 1 &- -%--t
MFIRELAY IGNITIONSWITCH (IGl)
AIR FLOW EXNSOR,,2,\VCLLW7nwmAm
m 468 1ES 1
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ENGINE
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KX35AC-H0538A-NM
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