light MITSUBISHI 3000GT 1991 Owner's Guide

13-158CRUISE CONTROL SYSTEM - Specifications
CRUISE CONTROL SYSTEM
SPECIFICATIONSLJGENERAL SPECIFICATIONS
MlOCA-.Rated load A
Voltage drop V
Auto-cruise control switchRated load A
SET
Stop light switch (for cruise control)Rated load A
Clutch switchRated load A
Vacuum pump
TypeRated load A
Control valve, release valveSERVICE SPECIFICATIONS
MlBCB- -
ItemsI Specifications
Accelerator cable playmm (in.)

Throttle cablemm (in.)
Cruise control cablemm (in.)
Resistance between terminals for control valve and reliefvalve in vacuum pumps1
O-l (O-.04)
2-3(.08-.12)
1-2 (.04-.08)
l-2(.04-.08)
50-60
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CRUISE CONTROL SYSTEM - Troubleshootina13461
Trouble symptom
l The set vehicle speed variesgreatly upward or downward.l “Hunching” (repeated alter-
nating acceleration and
deceleration) occurs after
setting is made.
Probable cause
Check chart No.Remedy
Malfunction of the vehicleNo. 4Repair the vehicle speedspeed sensor circuit
sensor system, or replacethe part.Malfunction of thespeedometer cable orspeedometer drive gear
Vacuum pump assembly
No. 5Repair the actuatorcircuit poor contact
system, or replace thepart.Malfunction of thevacuum pump assembly
(including air leaks from
negative pressure
passage)
The cruise control system is notcanceled when the brake pedal
is depressed.Malfunction of the ECU
-Replace the ECU.
Brake switch (for cruiseNo. 6Repair the harness or
control) malfunction
replace the stop light
(short-circuit)switch.
Vacuum pump assemblyNo. 5Repair the harness ordrive circuit short-circuitreplace the vacuum pump
assembly.
The cruise control system is notcanceled when the clutch pedalis depressed. (It is canceled, however, whenthe brake pedal is depressed.)Malfunction of the ECU
-Replace the ECU.
Damaged or disconnected
If the input checkRepair the harness, orwiring of clutch switchcode No. 26 indicatesrepair or replace the clutch
input circuita malfunction.switch.No. 7Clutch switch improper
installation (won’t switch
ON)
Malfunction of the ECU-Replace the ECU.
The cruise control system is notDamaged or disconnectedIf the input checkRepair the harness, or
canceled when the shift lever iswiring of inhibitor switchcode No. 26 indicatesrepair or replace themoved to the “N” position.
input circuita malfunction.inhibitor switch.
(It is canceled, however, when
No. 8
the brake pedal is depressed.)Improper adjustment of
inhibitor switch
Cannot decelerate by using the
SET switch.Malfunction of the ECU
Temporary damaged ordisconnected wiring of
control switch input
circuit
-
No. 2Replace the ECU.
Repair the harness orreplace the control switch
Vacuum pump assemblyNo. 5Repair the harness orcircuit poor contactreplace the vacuum puml:assembly.
Malfunction of thevacuum pump assembly
Malfunction of the ECU
-Replace the ECU.
NOTEECU: Electronic control unit
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13-162CRUISE CONTROL SYSTEM - Troubleshooting
Trouble symptomProbable causeCheck chart No.
Remedy
Cannot accelerate or resume speedOpen or short circuit in
No. 2by using the RESUME switch.RESUME switch circuit inReplace the control switch
control switch
Vacuum pump assemblyNo. 5circuit poor contactRepair the harness or
replace the vacuum pump
Malfunction of thevacuum pump assembly
(including air leaks
from negative pressurepassage)assembly.
Malfunction of the ECU-Replace the ECU.
Even when CANCEL switch is set toON, cruise control is not canceled
Open or short circuit
in CANCEL switchIf the input check
Replace the control switch
(Cruise control, however, iscode No. 27 indicatescircuit in control switch
canceled when brake pedal isa malfunction.
depressed.)No. 2
Malfunction of the ECU-Replace the ECU
The cruise control system can be set
Malfunction of theNo. 4while traveling at a vehicle speedvehicle-speed sensorRepair the vehicle speed
of less than 40 km/h (25 mph), or
circuitsensor system, or replace
there is no automatic cancellationthe part.
at that speed.Malfunction of thespeedometer cable orthe speedometer drive
gear
Malfunction of the ECU
-Replace the ECU.
The cruise control indicator light
No. 3
of the combination meter does notDamaged or disconnectedbulb of indicator lightRepair the harness or
illuminate. (But cruise controlreplace the light bulb.
system is normal)Harness damaged or
disconnected
Malfunction of the ECU
-Replace the ECU.
Cruise control ON indicator light
No. 3
does not come on. (However, cruiseBurned-out indicator lightbulbRepair the harness or
control is functional.)replace the main switch.
Open or short circuit in
harness
Malfunction of control functionby
ON/OFF switching of ELC 4 AA
accelerator switch.
(Non-operation of damper clutch,
2nd gear hold, etc.)
Overdrive is not canceled during
fixed speed driving
No shift to overdrive during
manual driving.
Malfunction of circuitrelated to acceleratorswitch OFF function
Malfunction of the ECU
Malfunction of circuit
related to overdrive
cancellation, or mal-
function of ECU
No. IO
No. 11Repair the harness or
replace the part.
Repair the harness or
replace the part.
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CRUISE CONTROL SYSTEM - Troubleshooting13-165
I I3Inspection of indicator light circuitI
CRUl
MAIN-!;$ROLIGNITIONSWITCH(IG1)
l-
CRUISE
CONTROL UNIT
Trl
b!XXSS-AK-RI303
DESCRIPTION OF OPERATION1. Cruise control ON (ASC ON) indicator light
Located in the combination meter, it lights as soon as the main switch is set to ON.
2. Cruise control (CRUISE) indicator light
During cruise control operation, transistor
Tr, in the control unit is kept in the ON state to keep the
indicator light on.
TROUBLESHOOTING HINTSECU terminal voltage
TerminalNo.Signal nameCondition
I
Terminal
voltage
I
23
I I
fr;se control (CRUISE) indicatorWhen cruise control is activeSystem voltage
When cruise control is inactiveov
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13-168CRUISE CONTROL SYSTEM - Troubleshooting,I
I 6 IInspection of stop light switch circuitIIIII
FUSIBLE LINK@
IDESCRIPTION OF OPERATIONIJ iWhen the brake pedal is depressed during vehicle
speed control, the cruise control (NC) contact of the
stop light switch is opened to interrupt the power
supply to the vacuum pump assembly for
cancella-tion of vehicle speed control. (Refer to P. 13-I 67.) At
the same time, the stop light (NO) contact is closed.
As a result, a cancel signal is input to the control unit
which internally interrupts the vacuum pump
assembly drive circuit.
TROUBLESHOOTING HINTSECU terminal voltage
Terminal
No.Signal nameConditionTerminal
voltage
15Stop light
switchWhen brake pedal
is depressedSystem
voltage
When brake pedal
is not depressed
OVh
”z15d
El 1’STOP
LIGHT
xx35-AX-R1305
7Inspection of clutch switch circuit
CRUISEc!$;ROLDESCRIPTION OF OPERATIONWhen the clutch pedal is depressed during vehicle
speed control, the contact of the clutch switch is
closed. As a result, a cancel signal is input to the
control unit which internally interrupts the power
supply to the vacuum pump assembly drive circuit
for cancellation of vehicle speed control.
TROUBLESHOOTING HINTSECU terminal voltage
II,Terminal
Signal nameConditionTerminal
No.voltage
1Clutch switchWhen clutch pedalOVis depressed
When clutch pedal System ,
is not depressedvoltage
d
KK35-AK-R130TA
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13-172CRUISE CONTROL SYSTEM - Troubleshooting
SELF-DIAGNOSIS CHECKING
Self-diagnosis checking is performed when there has been an
automatic cancellation without cancel switch operation.
‘1 ’
NOTE‘LAEven when the ignition key is placed in the OFF position, all
diagnosis codes are stored and retained, until the battery cable
is disconnected, to make sure that the problems encountered
in the past can be checked.
Control switch
1 RESUME
itch: ON
t
4SET switch:
ON
07FOO17
-\16FO2461
WITH MULTI-USE TESTER(1) Read the self-diagnosis code.
(2) Refer to the diagnosis chart and repair the defective point.
(3) Clear the self-diagnosis codes by the following procedure.@ Place the ignition switch in the ON position.@ With the SET switch in the ON state, set the main
switch to ON. In less than 1
.O second thereafter, set the
RESUME switch to ON.@ With the SET switch in the ON state again, keep the
’stop light switch in the ON state for more than 5dseconds.@ Check the self-diagnosis code to verify that a normal
code is output.
WITH VOLTMETER
(1) Connect an analog voltmeter across the self-diagnosis
output terminal and ground terminal of the diagnosis
connector.
(2) Place the ignition switch and main switch in the ON
position.
(3) Read the self-diagnosis code on the basis of the deflection
of the pointer of the voltmeter.
(4) Refer to the diagnosis chart and repair the defective point.
(5) Clear the self-diagnosis codes in the same way as when a
multi-use tester is used.
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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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CRUISE CONTROL .SYSTEM - Troubleshooting13-177
DASH PANELJunction block
JUNCTION BLOCKFront side
36FOOO236FOOO3
i
10 Clutch pedal switch 11 Stop light switch
12 Clock spring
13 Accelerator pedal switch
LOCATION OF CONTROL UNIT
E%sQ/I.LIlll-I BCrutse
!tcontrol
unit
GROUND POINT14 Over drive switch
15 Cruise control unit16
l 7
1
Front wiring harness and junctionl 8 block combination
19 Adapter wiring harness and junction block
combination
Body wiring harness
(LH) and junction block
I-\ --*
I d
4tT
-G
1
q\ ($$ 16F02E
36FOO18
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13-I 78CRUISE CONTROL SYSTEM - Service Adjustment ProceduresSERVICE
ADJUSTMENT PROCEDURESCRUISE CONTROL CABLES INSPECTION AND ADJUSTMENT
I
MlSFTCA
‘\J ~
Cruise control actuator
Cruise control assemblyAdjusting nut A
Link B
.
Adillstinn nr~+ R\Cruise control
cable
Adjusting nut C
Accelerator cable
Throttle valve-Link A
07N0004(1) Set the air conditioner, lights and other switches to OFF for
inspection at no load.
(2) Let the engine warm up until it runs at idle.
(3) Check that the idle speed is within the specified range.
(4) Stop the engine and set the ignition switch to OFF.
(5) Check that the accelerator cable, cruise control cable and
throttle cable are routed without sharp bends.
(6) Depress the accelerator pedal to check that the throttle
lever moves smoothly from the fully-closed to fully-opened
position.
(7) Check the free travel state of the inner cables of the
accelerator cable, cruise control cable and throttle cable.
(8) If the inner cables are too loose or have no free travel at all,
check using the following procedure.@ Remove the’ link protector.
@ Loosen the adjusting and lock nuts of the throttle lever
and intermediate links A, B and C to place the throttle
lever and intermediate links A, B and C in the free state.
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CRUISE CONTROL SYSTEM - Service Adjustment Procedures13-179Adjusting nut C
07NOOlELink Blever
07N0019Link
B07NOOlE
y,jj--ww ,03LO122
\\ \18FO2.2'@ Set the ignition switch to ON (do not start the engine).@ Rotate intermediate link C in the direction shown until it
is blocked by the stopper, turn down adjusting nut C in
the direction that the free travel of the inner cable is
reduced, and back off adjusting nut C the specified
number of turns just before intermediate link C begins
to move.
Amount adjusting nut C is to be backed off:
About l/2 turn [inner cable free travel0
- 1 mm (0 - .04 in.)]
About two turns [inner cable free
travel 2 to 3 mm
(.08 to .12 in.)]@ Secure the accelerator cable with the lock nut.@ Turn down adjusting nut B in the direction that the free
travel of the inner cable of the throttle cable is reduced.
At the position where the lever of intermediate link B is
brought into contact with intermediate. link C, back off
adjusting nut B the specified number of turns.
Amount adjusting nut B is to be backed off:
About one turn [inner cable free travel 1 to 2 mm
(.04 to .08 in.)]@ Secure the throttle cable with the lock nut.@ Secure the adjusting bolt of the surge tank.@ Turn down adjusting nut A in the direction that the free
travel of the inner cable of the cruise control cable is
reduced. At the position where the lever of intermedi-
ate link A is brought into contact with intermediate link
B, back off adjusting nut A the specified number of
turns.
Amount adjusting nut A is to be backed off:
About one turn [inner cable free travel 1 to 2 mm
(.04 to .08 in.)]@ Secure the cruise control cable with the lock nut.@ After adjustment, check to see that the end of the fixed
SAS is in contact with the stopper of the throttle lever.
CRUISE CONTROL SYSTEM INSPECTION
MlBFlDA
CRUISE CONTROL MAIN SWITCH CHECK
(1) Turn the ignition key to ON.
(2) Check to be sure that the CRUISE CONTROL ON indicator
light within the combination meter illuminates when the
main switch is switched ON.
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