1991 MITSUBISHI 3000GT sport mode

13-88FUEL SYSTEM - On-vehicle Inspection of MPI Components
MUFFLER MODE CHANGEOVER SWITCH
Engine control unit
r
@ Equipment sideconnector3
-Muffler
modeOFF changeover
ONswitch
2
r
7FU1053
OPERATIONlIf the operator turns the muffler mode changeover switch to ON or OFF position, this is converted to
high/low voltage to be sent to the engine control unit. Receiving this signal, the engine control unit
performs the dual mode (TOUR/SPORT mode) muffler control.
lThe output terminal of the muffler mode changeover switch has battery voltage applied to it from the
engine control unit through the resistor inside the unit. Place the muffler-mode changeover switch to the ‘LJj
ON posrtton, and the muffler mode changeover switch circuit will be closed to short the voltage applied
output terminal to the ground.. Accordingly, the output voltage of the muffler mode changeover switchchanges from high to low.
INSPECTION
Using Multi-use Tester
FunctionItem No. Data displayCheck conditionMuffler mode changeover Normal displayswitch condition
Data list35Switch
conditionIgnition switch: ONTurn to TOUR mode
Turn to SPORT modeON
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15-4INTAKE AND EXHAUST -Troubleshooting (Active Exhaust System)
TROUBLESHOOTING (ACTIVE EXHAUST SYSTEM)MlSEBAA
TROUBLESHOOTING PROCEDURE(1) Make sure that the valve operating cable is not dislocated.
(2) Make sure that the connectors of each component are positively connected and that no fuse has blown.
(3) Have an overall understanding of the substance and procedure of checking by reference to the
Troubleshooting Quick-Reference Table and perform check in the proper sequence.
(4) Check each component with its connectors disconnected.
TROUBLESHOOTING QUICK-REFERENCE TABLEIf no abnormality is found in all parts by the check performed in the following sequence, the problem is
probably caused by faulty active exhaust control unit and therefore the active exhaust control unit is replaced.
Se-Part to becheckedCheckingprocedureJudgement
Probable causeluenceRemedy
Normal
Abnormal
1ValveOperate valve
manually.Operates freely.Does not operate.Valve stickingReplace mainmuffler.
2ActiveRefer to P.15-34.exhaustFaulty switchReplace switch.
switch
3PowerwindowCheck continuity
between terminalsContinuity presentNo continuity
Faulty power
relay
@and @of
relay.window relayReplace power
window relay.
With battery voltage
applied between
terminals @and
@of relay, check
continuity between
terminals
@ and @of relay.
4
Actuator
Check contrnuityassembly
between terminalsNO continuity present
between terminalsContinuity present
between terminals
in SPORT mode.@and 0.@and 0.
Continuity present
between terminalsNo continuity present
between terminals
@and
0.@and 0.
Check continuity
between terminalsContinuity present
between terminalsNO continuity presentbetween terminalsFaulty actuator
Replace actuator
while idling in
@and 0.@and @assemblyassembly.
TOUR mode.NO continuity present
between terminalsContinuity present
between terminals
@and
0.@and 0.
Apply battery
Motor operates.Motor does not
voltage between
terminals @andoperate.
0.Motor turns inMotor does not
reverse directionturn.when polarity is
reversed.
5CableOperate activeBroken orexhaust switchActuator operates
and valve operatesActuator operates,
but valve doesReplace or adjust
(while idling)
as well.not work.maladjusted cable cable
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INTAKE AND EXHAUST -Troubleshooting (Active Exhaust.System)15-5
ACTIVE EXHAUST SYSTEM CIRCUIT CHECK
5= i C-82
-i
@g
0J/S1%
‘I
‘6 c-71
3
1
+RHEOSTATmACTUATOR
1::ASSEMBLYF-29
&$jq
ACTlYEFXoQBIlBZ"NIT
TROUBLESHOOTING HINTSChecking Active Exhaust Control Unit
TerminalNo.Signal
StatusTerminal voltage
1SPORT MODE signal
SPORT MODENot less than IOV
I-2 TTOUR MODE signal
TOUR MODENot less than IOV
Full open posrtion detection srgnalSPORT MODE(Not lesi’than 5V)
Engine control unit output signal
Control unit ground
Control unit groundTOUR MODE, engine speed of not lessthan 3,500 rpm
TOUR MODE, idle
SPORT MODE
At all times
At all
trmesBattery voltage
ov
Battery voltage
ov
Battery voltage
IFull close position detection signalTOUR MODE(Not lesk?than 5V)
I9Intermediate position detection signalAt all timesNot less than 5V
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I,
ELECTRONIC CONTROL SUSPENSION (ECS) - ;;~i%:~ustment339-15
Item No.Check
PointCheck ConditionSoundness Determination Value
24
Check by actually operating
vehicle.Speedometer indication and
MUT indication coincide.
26
61
62
63
64Vehicle
speed
sensorstop
lightswitch
F.R.actuator
F.L.actuator
R.R.actuator
R.L.actuatorDepress brake pedal.
ON
Do not depress brake pedal.OFF
Tour mode with vehicle stationarySOFT
Sport mode with vehicle stationaryHARD
Tour mode with vehicle stationarySOFT
Sport mode with vehicle stationaryHARD
Tour mode with vehicle stationarySOFT
Sport mode with vehicle stationaryHARD
Tour mode with vehicle stationarySOFT
Sport mode with vehicle stationaryHARD4. ACTUATOR CHECK
(I) Using the MUT, force-drive the actuator and fix the damping force changeover.
(2) Check service data (Item No. 61 through 64) to verify that the actuator has been force-driven.
NOTE
lAll of the four actuators in the shock absorbers are simultaneously changed over by forced drive.
lThe damping force changed over and fixed by forced drive is cleared by the following three conditions.1. Ignition switch OFF
2. Vehicle speed 3 km/h (1.9 mph) or more
3. MUT disconnected
Actuator Check List
Item No.Check Point
Check ConditionMUT Service Data Item
No. 61 - 64 Indicated
01Damping force SOFT
03Damping force MEDIUM
04Damping force HARD
Vehicle in stationary
conditionSOFT
MEDIUM
HARD
i
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33B-18ELECTRONIC CONTROL SUSPENSION (EC9 - ~::::u:?‘s*men*
\/I
I(Front)(Rear)I
12FOOG
6. ACTUATOR OPERATION CHECKM33FJAA
6-1. Actuator Operating Sound Check
(I) Set the ignition switch to ON.
(2) Bring your ear near the top of the shock absorber.dNOTE
In the case of the rear shock absorbers, remove the trim
cover at the top of the shock absorber before bringing your
ear near the shock absorber.
(3) Check that the operating sound of the actuator in the shockabsorber can be heard each time the control modes are
changed by pressing the ECS switch.
6-2. Damping Force Check(1) Set the ignition switch to ON.
(ECS indicator Tour ON, damping force SOFT)
(2) Check the damping force SOFT state by shaking the top
mounting points of the front shock absorbers or the top ofthe rear end panels of the rear shock absorbers up and
down.
(3) Press the ECS switch to change the control mode to Sport.(ECS indicator Sport ON, damping force HARD)
(4) Shake the vehicle up and down to check that the dampingforce is harder than in the SOFT state.
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