display MITSUBISHI 3000GT 1991 Owner's Manual

FUEL SYSTEM - On-vehicle .lnspection of MPI Components13-111
INSPECTIONUsing Multi-use Tester
FunctionItem No. Data display
Data reading 45
Stepper
1
motor steps
~
Check condition
l Engine coolant tem-
perature: 80 to 95°C
(176 to 205°F)
0 Lamps, electric cooling
fan, accessory units:
All OFFl Transaxle: Neutral(P range for vehiclewith AA>l Steering wheel: Neutrall Idle position switch: ON(compressor clutch
to be ON if air condi-
tioner switch is ON)l Engine: idling
Load stateStandard value
;;rnditioner switch:2 - 12 stp&conditioner switch:
25 - 65 stp
l $irNconditioner switch:15 - 63 stp0 Selector lever:Shift to D range
NOTEWhen the vehicle is new [within initial operation of about 500 km (300 miles)], the stepper motor steps may be about 30steps more than standard.
CautionWhen the selector lever is shifted to the “D”range, the brakes must be used to prevent the vehicle frommovingforward.
03A020
Using Oscilloscope(1) Connect the probe to each oscilloscope pick-up point as
shown in the circuit diagram.
(2) Start the engine.
(3) When the air conditioner switch is turned on, the idling
speed increases to operate the idle speed control. Check
the instantaneous waveform.
NOTEKeep in mind that the waveform can be observed only
when idle speed control is in operation.
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13-116FUEL SYSTEM - 0
n-vehicle Inspection of MPI Components
INSPECTION
Using Multi-use Tester
(d
FunctionItem No. Data displayCheck condition
Engine state
Standard valueData reading 44
Ignitionadvancel Engine: Warming up
750 rpm (Idle)7 - 23”BTDCl Timing light: Set (settiming light to check2,000 rpm30 - 40”BTDC actual ignition timing)28 - 35”BTDC

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Function
Data listItem No.Data displayCheckTerminalStandard value
condition
condition
36Continuity present or
not present betweenl Engine:
IdlingIgnition timing ad-ON
ignition timing adjustmentjustment terminal isterminal and groundgrounded
Ignition timing ad-OFFjustment terminal is
disconnected from
ground
Function
Actuator testItem No.
DriveCheck conditionNormal condition
17Set to ignition timingl Engine: idling5”BTDCadjustment model Timing light: set\
($Gizi)
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Normal waveform03AO207
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Normal waveform
Using Oscilloscope1. Primary signal of ignition coil
(I) Run the engine at an idle revolution speed.
(2) Connect the probe to oscilloscope pick-up point 1 as
shown in the circuit diagram, and check the primary
signal of the ignition coil.
2. Control signal of power transistor
Connect the probe to oscilloscope pick-up point
2 as shown
in the circuit diagram, and check the control signal of the
power transistor.
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FUEL SYSTEM - On-vehicle lnwection of MPI ComDonents13-121
LEGR CONTROL SOLENOID VALVE - Non Turbo, Turbo>MlBYZBAControl relav
EGR control
solenoid valve@ Equipment side
connector
Engine
control
unitEngine control unit connector
7FUO653
OPERATION
lThe EGR control solenoid valve is a duty control type solenoid valve. It makes control by leaking EGR valve
operating negative pressure to the throttle body A port.
lPower supply from the battery is sent through the control relay to the EGR control solenoid valve. When
the engine control unit turns off the power transistor inside the unit, current no more flows through the
coil and EGR valve operating negative pressure leaks.
TROUBLESHOOTING HINTIf the results of EGR control solenoid valve on-vehicle and off-vehicle inspections are normal but the
self-diagnosis code for EGR system failure is displayed, check the EGR valve, vacuum hose and EGR passage
for blocking.
c.
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13-134FUEL SYSTEM - On-vehicle InsDection of MPI ComDonents
INSPECTIONUsing Multi-use Tester
FunctionItem No. Data displayCheck condition. Driving conditionStandard valueData reading 45
Stepper
Engine warmed up
Apply fairly sharp
To reach tempo-motor stepbraking at 50 km/h
rarily 70 to
(4th speed) to100 stepsstop vehicle
NOTESelect a place where a rear-end collision is unlikely.
HARNESS INSPECTION
side connector
Engine control umtharness side connecm
6FU1543
Check for an open-circuit or a short-circuit to ground, between the ABScontrol unit and the engine controlunit.l
ABS control unit connector: Dis-connectedlEngine control unit connector:
Disconnected7Repair the
harness.
(@m-ml)
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CRUISE CONTROL SYSTEM - Troubleshooting
DIAGNOSIS DISPLAY PATTERNS AND CODES
13473
CodeDisplay patterns (output codes)Probable causeCheck chart No.No.(Use with voltmeter)
11l-l n-JILL
The same pattern repeatedly displayed
Vacuum pump assembly drive output systemout of order5
I I12Vehicle speed signal system out of orderI4I
I In
Control switch out of order (When SET or2RESUME switch is kept in ON statecontinuously for more than 60 seconds)
Control switch out of order
Throttle position sensor or idle switch out9
of order
Normal code
12AOlOa
NOTE
1. When two or more problems occur simultaneously, the
three latest code numbers are displayed in the order of
lowest code number first.
2. Even if the problem represented by the code number
marked * occurs during cruise control operation, the cruise
control mode will not be canceled.
3.When the system is normal, the diagnosis code is displayed
as described below.@ If a multi-use tester is used:
“NORMAL!
! I’ will be displayed.@ If a voltmeter is used:
Continuous ON/OFF signals will be displayed at 0.5
second intervals. (Refer to the illustration at the left.)
INPUT CHECKINGInput checks should be made when the cruise control system
cannot be set and when it is necessary to check (when a
malfunction related to the cruise control system occurs)
whether or not the input signals are normal.
NOTE
1.If inspection of self-diagnosis is necessary, confirm diagno-
sis code first and conduct input check.
2. Input check can be conducted by set operations.
Self-diagnosis terminal outputs display patterns.
3. Display codes are displayed only if the circuit is normal
according to the conditions shown in the table on the next
paw.Perform checks using the following procedures.
(1) Connect a multi-use tester or a voltmeter to the diagnosis
inspection connector of the junction block.
NOTEConnect a voltmeter using the same procedure as for
inspection of diagnosis output.
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13-174CRUISE CONTROL SYSTEM - Troubleshooting
(2) Calling up a code
Control switch
SUME
itch: ON
t
4SET switch:
ON@ Set the ignition switch to ON.@ With the SET switch in the ON state, set the main
switch to ON. In less than 1
.O second thereafter, set theI,/RESUME switch to ON. Then the input check results
can be displayed.
07FOO17 I(3) Reading a code@ Perform the individual input operations according to the
input check table and read the codes.
NOTE1. When two or more input operations are performed
simultaneously, all the associated code numbers are
output in ascending order.
2.If no code is output by performing any of the input
operations, the control unit power supply circuit or
SET and RESUME switches are probably defective.
Check the check tables 1 and 2
(P.13-163, 164).
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CRUISE CONTROL SYSTEM - Troubleshooting
INPUT CHECK TABLE
odeDisplay patterns (output codes)Input operationCheck results40.(use with voltmeter)
21SET switch ONSET switch circuit normal
n
22RESUME switch.ONRESUME switch normal
23
nn
Stop light switch ON(brake pedal depressed)
Stop light switch circuit normal
24Vehicle speed more than approx.
40 km/h (25 mph)Vehicle speed sensor circuitnormal if code Nos. 24 and 25
are displayed
25Vehicle speed less than approx.
40 km/h (25 mph)
26M/T
Clutch switch ON
-1~ ~~;~~o~~i~~~~;sed’
(SELECT lever placedin “N” position)Clutch switch circuit normal
Inhibitor switch circuit normal
27CANCEL switch ONCANCEL switch circuit normal
TPS output voltage 1.5 V or more
Throttle position sensor circuit
(Accelerator pedal depressed more normal
than half the way)
Idle switch OFF (Accelerator pedalIdle switch circuit normal
depressed)@ Set main switch to OFF.
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23-24AUTOMATIC TRANSAXLE - Troubleshooting
FAULT CODEDESCRIPTIONCode
No.Display PatternItemRemedial Action
Excessively large throttle
position sensor outputl Check throttle position sensor
connector.
l Check throttle position sensor
on bench.
12Excessively small throttle
position sensor outputl Adjust throttle position sensor.
l Check accelerator switch
(whether code number 24 is being
output).
13Defective or improperly
adjusted throttle position
sensor
14
Improperly adjusted throttle
position sensor
Open-circuited low-oil-
temperature sensorl Check oil temperature sensor
connector.
l Check oil temperature sensor on
bench.
16Short-circuited high-oil-
I-lMnnM-.temperature sensor
17
Open-circuited high-oil-
rlnnnruuvltemperature sensor or short-
circuited low-oil-temperature
sensor
Open-circuited kickdown servo
switch
Short-circuited kickdown servo
switchl Check kickdown servo switch
connector.
l Check kickdown servo switch on
bench.
Open-circuited ignition pulse
pickup cablel Check ignition pulse signal line.
24Open-circuited or improperly
adjusted accelerator switchl Check accelerator switch connector
l Check accelerator switch on bench.
l Adjust accelerator switch.
12A010412A0107
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AUTOMATIC TRANSAXLE - Troubleshooting23-25
L
L
ZodeNo.
31Display Pattern
ItemRemedial Action
Open-circuited pulse generator Al Check pulse generator A or B on
bench.
32l Check vehicle-speed reed switch
(chattering).
Open-circuited pulse generator B
Open-circuited shift control
solenoid valve Al Check solenoid valve connector.
l Check shift control solenoid valve
A on bench.
42Short-circuited shift control
solenoid valve A
Open-circuited shift control
solenoid valve Bl Check solenoid valve connector.
l Check shift control solenoid valve
B on bench.
Short-circuited shift control
solenoid valve B
45
uuuLNulM-Open-circuited pressure controll Check solenoid valve connector.
solenoid valvel Check pressure control solenoid
valve on bench.
46Short-circuited pressure
control solenoid valve
Open-circuited damper clutch
control solenoid valvel Check solenoid valve connector.
l Check damper clutch control
solenoid valve on bench.
Short-circuited damper clutch
control solenoid valve
49Defective damper clutch systeml Check damper clutch hydraulic
circuit.
lllJl!-l Check damper clutch control
solenoid valve on bench.0 Replace control unit.
12A010712A0105
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23-26AUTOMATIC TRANSAXLE - Troubleshooting
Code
No.Display PatternItemRemedial Action
1 st speed shift not finishl Check connectors of pulse
generators A and
B.l Check pulse generators A and B on
bench.
l Rear clutch slipping
52
uuuuu-ln-2nd speed shift not finishl Check connectors of pulse
generators A and B.
l Check pulse generators A and B on
bench.
l Rear clutch slipping
533rd speed shift not finishl Kickdown brake slipping
l Check connectors of pulse
generators A and B.
4th speed shift not finishl Check pulse generators A and B on
bench.
l Front clutch slipping
l Rear clutch slipping
l Check connectors of pulse
generators A and B.
l Check pulse generators A and B on
bench.
l End clutch slipping
6162l Kickdown brake slipping
Short-circuited torque
reduction request signal linel Check torque reduction request
or open-circuited torquesignal line.
reduction execution signal linel Check torque reduction execution
signal line.
Open-circuited torque reduction
request signal line0 Check torque reduction request
signal line.
63Short-circuited torque
reduction execution signal linel Check torque reduction execution
signal line.
12A0106
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