diagram MITSUBISHI 3000GT 1991 User Guide

iFUEL SYSTEM
- On-vehicle Inspection of MPI Components
INSPECTION
Using Oscilloscope13-71
::Normal waveform(1) Run the engine at an idle speed.
(2) Connect the probe to the oscilloscope pick-up point as
shown in the circuit diagram, and check the waveform.
7Fuo495HARNESS INSPECTION
= 7FUO496r
i2
@ Harness sideconnectorF
7FUO497
J
Measure the power supply voltagel Connector: Disconnected
l Ignition switch: ON
Voltage
(VI, OK(I:
sv
ib
02
Repair the
harness.
(@m - Con-
trol relay)
ICheck for continuity of the groundcircuit.l Connector: Disconnected
3
~,
Check the voltage of the output err-cuit.l Connector: Disconnected
l Ignition switch: ON
Voltaae
(V)4.8
- 5.2Repair the
harness.
(@El-ED
I7FUO498
idliTSB Revision

FUEL SYSTEM - On-vehicle Inspection of MPI Components13-73
INSPECTION
Using Multi-use Tester
FunctionItem No. Data displayCheck conditionCheck content
Normal stateData reading 22
Crankingl Engine cranking
Compare cranking speedIndicated speed
speedl Tachometer connectedand multi-use tester(check on and off ofto agree
reading
primary current of
ignition coil bytachometer)
NOTE(1)The tachometer indicates a third of the actual engine speed. Therefore, 3 times the tachometer indication is theactual engine speed.(2)When the tachometer is set to the 2-cylinder range, it indicates actual engine speed.
FunctionItem No. Data displayCheck conditionCoolant temperatureStandard value
Data reading22Idle speedl Engine: Running atAt -20°C (-4°F)1,300 - 1,500 rpm
idle
l Idle position switch:ONAt 0°C (32°F)At 20°C (68°F)
At 40°C (104°F)
At 80°C (176°F)1,250
- 1,450 rpm
1
,I 00 - 1,300 rpm
950-1,150rpm
600 - 800 rpm
-m-2,-5v
f-lov
---Normal waveform
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.
1 TSB Revision

FUEL SYSTEM- Ori-vehicle lnwection of MPI ComDonents13403
+/A+ A: Injector drive time
Normal waveform03A0201
HARNESS INSPECTION
--J1
Harness side
7FlJO669
* I
@
Harness side
connector
1 HarnessJPside =connector7FUO805
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 at
the drive side of each injector.
Measure the power supply voltage of
the front bank injector.
-
l Connector: Disconnectedl Ignition switch: ON
1
Repair the
harness.
(m-Control relay)
Measure the power supply voltage ofthe rear bank injector.
l Connector: Disconnectedl Ignition switch: ON
Voltage
(VI
svRepair the
harness.
(m - Con-
trol relay)
Check for an open-circuit, or a
short-circuit between the front bank injectorand the engine control unit.
l Injector connector: DisconnectedlEngine control unit connector:
Disconnected
id
TSB Revision

13-106FUEL SYSTEM - On-vehicle Inspection of MPI Components
INSPECTION
Using Multi-use Tester
FunctionItem No.Data displayCheck conditionCoolant temperatureStandard value‘L,,,J
DataDrive time*’0°C (32’F)*’readingiRea:bankiEngine: CrankingApprox. 53 ms
(FronT7bank)20°C (68°F)
Approx. 29 ms
80°C (176°F)Approx. 7 ms
FunctionItem No.
Data displayCheck conditionEngine stateStandard value
Datareading(Reaebank)Drive time*3l Engine coolant tem-700 rpm (Idle)1.9 - 2.5 ms
perature: 80 to 95°C
(Front7banki(176 to 205°F)2,000 rpm1.6 - 2.2 ms
l Lamps, electric coolingfan, accessory units:To increase
All OFFWhen sharp racing is
made
l Transaxle: Neutral(P range for vehicle
with A/T)
l Steering wheel: Neutral
NOTE“I : The injector drive time refers to when the supply voltage is 11 V and the cranking speed is less than 250 rpm.
“2: When coolant temperature is lower than 0°C (32°F). injection is made by four cylinders simultaneously.
“3: When the vehicle is new [within initial operation of about 500 km (300 miles)], the injector drive time may be about
10% longer.
Function
Actuator testItem No.
Drive contentCheck conditionNormal state
01No. 1 injector shut offEngine: Idling afterIdle state to changewarm-upfurther (becoming less
02No. 2 injector shut off(Shut off the injectorsstable or stalling)
03in sequence during afterNo. 3 injector shut offengine warm-up, checkthe idling condition)
04No. 4 injector shut off
05
No. 5 injector shut off
06
No. 6 injector shut off
\,iUsing
OscillqscopeI(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 at
the drive side of each injector.~
-
LJ
4 AL A: InjectorNormal waveformdrive time03A0209
TSB Revision

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.
1 TSB Revision

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

‘
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)
IJ
\LIOV _
ovep~,. ..~_~.~ fA t---.-
I
Normal waveform03AO207
(
j /’ II
IOV _I ’/
/ 1ovIJ
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.
TSB Revision

FUEL SYSTEM - Throttle Body13-145Orifice
Nipple (green)3EM05iGroundThrottle
positlonsensor output
Idle-position
switchTh>ottle position
sensor power7FUO535(5) Disconnect the hand vacuum pump and connect it to the
other nipple.
(6)Make sure that the negative pressure leaks out as soon as it
is applied.
CLEANING THROTTLE BODY PARTS
(1) Clean all throttle body parts.
Do not use solvent to clean the following parts:
l Throttle position sensor (Idle position switch)
l Idle speed control servo
If these parts are immersed in solvent, their insulation will
deteriorate.
Wipe them with cloth only.
(2) Check if the vacuum
pot-t or passage is clogged. usecompressed air to clean the vacuum passage.
SERVICE POINT OF REASSEMBLY
M13SGAN4. INSTALLATION OF THROTTLE POSITION SENSOR
(1) Set the throttle position sensor to the throttle body as
shown in the diagram.
(2) After turning the throttle position sensor 90” in the
clockwise direction to set it, tighten by turning the
screw.
(3) Connect the circuit tester between 1 (ground) and 3
(output), or between 3 (output) and 4 (power). Then,
make sure that the resistance changes smoothly when
the throttle valve is slowly moved to the fully open
position.
(4) Check for continuity across terminals 2 (Idle position
switch) and 1 (ground) with the throttle valve both fully
closed and fully open.
IThrottle valve positionIContinuityI
Fully closedConductive
Fully openINon-conductiveIIf there is not continuity with the throttle valve fully
closed, turn the counterclockwise direction, and then
check again.
(5) If the above specifications are not met, replace the idle
position switch.
1 TSB RevisionI

14-4COOLING - Troubleshooting
CIRCUIT DIAGRAM
FUSIBL
RADIATOR
FAN ASSEMBLY
(RADIATOR
,
FAN MOTOR>r{
!&w
F
A-04X ,---LINK0
J
0A
j
IGNITION
J/B
lxI
ti
51.: ,A-07X
J1
>II
ticpLi6
m
R&
b3
,2L-R1
RADIATOR FAN ASSEMBLYL!a ml
T
X35-AC-NWOl-NY
TSB Revision

23-32AUTOMATIC TRANSAXLE - Troubleshooting
INSPECTION OF ELECTRONIC CONTROL SYSTEM COMPONENTS
1. WiringBased on the wiring diagram.check whether the continuity andgrounding of each harness is OK.
I
(
4
ContinuityII
+
Normal~ Improper connection of
connector, damaged ordisconnected harness,
or incorrect wiring con-
nection.
I
Reconnect the connec-tor; repair or replace theharness.Vary the thermo-sensitive part
2. Oil-temperaturefrom low temperature to highsensortemperature and check theresist-Damaged or disconnected
ante between the terminals 1 anwiring2or2and3.
4
J
Changes of the resistance con-Replace the oil-
tinuous and smooth.temperature sensor
41750447
Normal1
1:LOW temperature side2: Ground
3:High temperature side
I:3. Throttle-
K
Check the resistance between
Ip~~~t,ion sensorterminals 1 and 4 of the TPS.hiah or infinitem- -----inecteciI-
\ IDamaged or discon-..----Awiring
I
c3.5 - 6.5 kW20”C (68°F)t
v
Replace the TPS.I>ITPS terminal
7FUO5351. Ground
2. Idle switch
3. output
4. Power
Check the resistance betweenterminals 4 and 2 with the engine
idling after throttle-valve opening
warm-up.
Resistance: approx. 0.4
kR/20°C (68°F)
Changes of the resistance con-
tinuous and smooth.
/Resistance:\more or less
than 0.4 kQ/Improper adjustment
Istallaiion.I
Check for changes of theresist-ance between terminals 4 and 2when the throttle valve is
operated from the idling position
o the fully open position.
Poor contactII
TSB Revision

33B-1
ELECTRONIC
CONTROL
SUSPENSION
CONTENTSM33AA-B
CIRCUIT DIAGRAM
22SPECIAL TOOLS........................................................................3
................................................................
DAMPING FORCE CHANGEOVERSPECIFICATIONS....................................................................2
ACTUATOR................................................................................20General Specifications.......................................................2
ECS CONTROL UNIT................................................................21Service Specifications.......................................................3
ECS INDICATOR LIGHT............................................................20STEERING ANGULAR VELOCITYa .
ECS SWITCH............................................................................
19
G SENSOR................................................................................
19
POSITION DETECTION SWITCH............................................20
SERVICE ADJUSTMENT PROCEDURES
............................
12
On-Vehicle Inspection........................................................12
SENSOR*....................................................................................-IY
STOP LIGHT SWITCH............................................................20
THROTTLE POSITION SENSOR
............................................20
TROUBLESHOOTING............................................................4
VEHICLE SPEED SENSOR....................................................
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
(I)A Supplemental Restraint System (SRS), which uses a driver-side air bag, has been installed in the 3000GT.(2)The SRS includes the following components: impact sensors, SRS diagnosis unit: SRS warning light, aiir bagmodule, clock spring, interconnecting wiring.Other SRS-related components (that may have 1:o be
removed/installed in connection with SRS service or maintenance) are indicated in the table of contents byan asterisk (*).
WARNING!(1)Improper service or maintenance of any component of the SRS, or any SRS-related component, can lead to
personal injury or death to service personnel (from inadvertent firing of the air bag) or to the driver (from
rendering the SRS inoperative).
(2) Service or maintenance of any SRS component or SRS-related component must be performed only at an
authorized MITSUBISHI dealer.(3) MITSUBISHI dealer personnel must thoroughly review this manual, and especially its GROUP
Ei2B -Supplemental Restraint System (SRS), before beginning any service or maintenance of any component of theSRS or any SRS-related component.