ignition MITSUBISHI 3000GT 1991 Manual PDF

CRUISE CONTROL SYSTEM - Troubleshooting13-163CHECK CHART
it l/Inspection of control unit power supply circuit
L;
,/
id
CRUISE#fi$ROL
0
SWITCH
“71
TROUBLESHOOTING HINTSECU terminal voltage
DESCRIPTION OF OPERATIONThe power is supplied through the ignition switch
(IG,) and cruise control main switch to the control
unit.
1. When the cruise control main switch is set to
ON with the ignition switch at ON, the current
from switch
S, flows through relay Ry, in the
switch. Accordingly, the contact of relay
Ry, is
closed and the power is supplied to the control
unit.
2. When the main switch is released, it automati-
cally returns to the neutral position. Since the
current from switch
S2 flows to relay Ry,, the
contact of relay Ry, remains closed.
3.When the main switch is set to OFF, current to
relay
Ry, is interrupted. This opens the contact
of relay
Ry, to stop the power supply to the
control unit. When the switch is released, it
automatically returns to the neutral position, but
relay Ry, stays in the OFF state.
4. When the ignition switch is set to OFF while
relay Ry, in the main switch is ON, relay
Ry, is
forced to the OFF state just like when the main
switch is set to OFF. Even if the ignition switch
is set to ON again, relay
Ry, stays in the OFF
state until the main switch is set to ON.
NOTEThe numbers beside each connector correspond
to those in the section
(P.13-176) “HARNESS
AND COMPONENTS LAYOUT”
TerminalNo.Signal nameCondition
I
TerminalvoltageI
2Control unit power supplyMain switch ON and neutral positionSystem voltage
thereafter
Main switch OFF and neutral positionov
thereafter8, 14
Control unit groundAt all timesov
16Control unit back up power supplyAt all timesSystem voltage
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13-164CRUISE CONTROL SYSTEM - Troubleshooting
2Inspection of control switch circuit
IGNITIONSWITCHtACC)
*X35-AK-R1302r-
._--------
LE- @CONTROL UNIT
TROUBLESHOOTING HINTSECU terminal voltage
DESCRIPTION OF OPERATIONdThe control switch is a switch in which the SET,
RESUME and CANCEL switches are integrated.
Therefore, different resistance values are used for
the individual switches to change the outputs
(voltages) to the control unit. Current flows through
fuse No. @ of J/B and through the control switch to
the control unit.
1. SET switchWhen the cruise control switch is ON, if the SET
switch is set to ON while vehicle speed is within
a range from about 40 to 145 km/h (25 to 90
mph), the vehicle starts cruising at the speed. If
the SET switch is kept at ON during cruise
operation, the vehicle coasts, and starts cruising
at the speed reached when the SET switch is
set to OFF.
2. RESUME switch
Even if cruise operation is canceled, the vehicle
resumes cruising at the speed set before the
cancellation. Both when the main switch is set
to OFF and when the vehicle speed is reduced
to less than 40 km/h (25 mph) , the vehicle will
not resume cruising at the previously set speed
even if the RESUME switch is set to ON. If the
RESUME switch is kept at ON during cruise
LJoperation, the engine accelerates, and the vehi-
cle starts cruising at the speed reached when
the RESUME switch was set to OFF. (However,
when the vehicle speed is raised to more than
145 km/h (90 mph), the vehicle cruises at
approximately 145 km/h {90 mph).
3. CANCEL switch
When the CANCEL switch is set to ON during
cruise operation, the cancel signal is input to the
control unit which internally interrupts the power
supply to the vacuum pump assembly for
cancellation of cruise operation.
18Control switchSignal name
L
Condition
I
Terminalvoltage1
When all switches are OFFIov1
When SET switch is ONI3vI
When RESUME switch is ON
When CANCEL switch is ON6Vd
Systemvoltage
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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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13466CRUISE CONTROL SYSTEM - Troubleshooting
I I4Inspection of vehicle speed sensor circuitI

IGNITIONSWITCH(IG1)
5”
El
CRUISE
CONTROL
3UNIT
cl!AI
g6pl!Ezq@zla
;i
d
“m ;ygmq%q
?
VEHICLE
SPEED
SENSOR
xX35-AR-RI304P
19Y
*
$
&
~E$iJ
0z
L
COMBINATION
METER
KX35-AK-Rl3Yla
DESCRIPTION OF OPERATION
The vehicle speed sensor, mounted in the transmission, delivers pulse signals proportional to the rotational
speed of the transmission output gear (vehicle speed) to the control unit. (Four pulse signals generated per
rotation of the output gear) Since the vehicle speed sensor is of the electronic type, the power is supplied
through the ignition switch (IG,).
The vehicle speed sensor is a reed switch type and is mounted in the speedometer. It sends pulse signals
proportional to the rotational speed of the transmission output gear (vehicle speed) to the control unit. (Four
pulse signals generated per rotation of the output gear)
TROUBLESHOOTING HINTSDiagnosis No. 12 (Automatically canceled)
ECU terminal voltage
1TerminalNo.I19
i
Signal nameCondition
Terminalvoltage
Vehicle speed sensor
Slowly drive forward with SELECT lever0 to
0.6Vat “D” or "1 st Speed”2J &l;;:neg
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LjlI~~
\
J1
l/j,

13-170CRUISE CONTROL SYSTEM - Troubleshooting
10Inspection of circuit associated with accelerator pedal switch OFF function
IGNITlOiiI sw1:
Ind
,277
?IOA-..A-"2Y
.
“3EL
3,"I\-
2
.-----------
E
r
r
g:-1
13--
ii
KH(IG2)
ORi13 : DI
"CLt-t-fi[T
UNIT
DESCRIPTION OF OPERATION‘\JThe accelerator pedal switch is used to detect the
operating state of the accelerator pedal. It is one of
the sensors of the
ELC4A/T automatic transmis-
sion. Since the accelerator pedal is not operated
during vehicle speed control,.the cruise control unit
forces transistor
Tr, into the OFF state, creating the
same state as when the accelerator pedal switch is
placed in the OFF state.
1
$iK&ERATOR
SWITCHH
1
2
-I
CRUISE
CONTROL
UNIT
TROUBLESHOOTING HINTSECU terminal voltage
TerminalNo.Signal name
Condition
3Accelerator pedal switch control
power supplyWhen ignition switch is placed at ON
9Accelerator pedal switchWhen accelerator pedal is depressed
When accelerator pedal is not depressed
System voltage
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CRUISE CONTROL SYSTEM - Troubleshooting13-171
11Inspection of circuits associated with overdrive cancel
!IGNITION
OVER
DRIVE
SWITCH
C2,
SW1
il-
'TCH(IG2)
14
,lO
l-l
CRUISE
tHTRO"
DESCRIPTION OF OPERATIONOn a vehicle with cruise control, the OD switch ON signal is input through the cruise control unit to the
ELC-4AIT control unit.
When the vehicle speed control is in the overdrive mode, if the actual vehicle speed falls more than about 7
km/h (4 mph) below the set vehicle speed, the cruise control unit forces transistor
Tr, into the OFF state. This
cancels the overdrive mode because no OD switch ON signal is input to the
ELC-4PJT control unit.
TROUBLESHOOTING HINTS
ECU terminal
voltage
TerminalSignal nameConditionTerminal
No.voltage
3OD signal control power supplyWhen ignition switch is ONSystem voltage
10ELC-4A/T control unitWhen overdrive mode is activeSystem voltage
When overdrive mode is inactiveov
11OD switchWhen OD switch is ONSystem voltage
When OD switch is OFFov
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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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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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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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