1989 MITSUBISHI GALANT clutch

13-336AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
Probable cause1 Check chart No.1 Remedy
l The set vehicle speed variesMalfunction of the ve-No.4Repair the vehicle speec
greatly upward or downward.hicle speed sensor cir-sensor system, or re-l “Hunching” (repeated alternatingcuit place the part.
acceleration and deceleration) oc-
curs after setting is made.
Malfunction of the spee-dometer cable or spee-dometer drive gear
Actuator circuit poor
contact
Malfunction of the ac-
tuator
No.5Repair the actuator sys-tern or replace the part.
Malfunction of the ECU
-Replace the ECU.
The auto-cruise control system is notDamaged or discon-If the input check codeRepair the harness or re
canceled when the brake pedals isnetted wiring of the stopNo.23 indicates a mal- place the stop light
depressed.light switch input circuit; function. No.6-1switch.
brake switch (for auto-
cruise control) malfunc-
tion (short-circuit)
Actuator drive circuit
No.5Repair the harness or reshort-circuit.place the actuator.
Malfunction of the ECU
-Replace the ECU.
-he auto-cruise control system is notDamaged or discon-If the input check codeRepair the harness, or:anceled when the clutch pedal isnetted wiring of clutchNo.23 indicates a mal- repair or replace thedepressed. (vehicles with a manual pedal position switchfunction. No.6-3
clutch pedal position
ransaxle)input circuit switch.
It is canceled, however, when the
)rake pedal is depressed.) Clutch pedal positionswitch improper installa-
tion (won’t switch ON)
Malfunction of the ECU-Replace the ECU.
-he auto-cruise control system is notDamaged or discon-If the input check codeRepair the harness, orzanceled when the shift lever isnetted wiring of park/No.23 indicates a mal- repair or replace thenoved to the “N” position. (vehicles
neutral position switch function. No.6-2park/neutral positionvith an automatic transaxle)input circuit switch.t is canceled, however, when theIrake pedal is depressed.)Improper adjustment of
park/neutral position
switch
Malfunction of the ECU-Replace the ECU.
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13-338AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
Trouble symptomProbable causeCheck chart No.Remedy
Malfunction of control function by
Malfunction of circuitNo. 7Repair the harness or
ON/OFF switching of ELC 4
A/Trelated to acceleratorreplace the part.
accelerator switch switch OFF function
(Non-operation of torque converterclutch, 2nd gear hold, etc.)
Malfunction of the
ECU
Overdrive is not canceled during
fixed speed driving.
Malfunction of circuitNo. 8Repair the harness or
related to overdrive
replace the part.
cancelation, or mal-
function of ECU
No shift to overdrive during man-
ual driving.
.
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Revision

AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
5.CHECKING THE ACTUATOR CIRCUIT
Electromannetic clutch coil Clutch @at’!Planetarv oinion
To junction block
fuse No. (9)
Ccdtnr riri\mchnftMainSun Cruise-
control
switchTo junction block
fuse No. (9)
Actuator
/ (15)
p$%Emig
jyl; _________________ ;F:;;:ght
z " (LG)-1( LG),l A ,l\BWI(17)
Diode2d 111n\
Actuator
ECU
(12)-+ E-l -
1610620
NOTENC: ON at all times
NO: OFF at all times
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13-344AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
Description of operation
* -LimA switch
DC motor
7 coil
-
1. When (with the main switch ON) the driver switches ON the SET switch when the pre-
scribed vehicle speed is reached, the control
unit sends current to the electromagnetic clutch
coil of the actuator, thus attracting the clutch plate, and also illuminating the auto-cruise in-
dicator light, Then, when the ring gear of the planetary pinion is secured, the control motor at
the same time causes the DC motor to be
switched ON, and the DC motor operates at high speed.
2.The rotation of the DC motor is, as described in
the illustration above, transmitted to the worm
gear, and thereafter to the worm wheel, the
sun gear, and the planetary pinion in that
sequence. Because the ring gear is secured at
this time, the planetary pinion rotates while revolving around the sun gear. Because the
planetary pinion is installed to the carrier, both
the carrier and the selecotr drive shaft unified
with it, as well as the selector, are caused to rotate.
3.The switching of the direction (PULL or REL.) of
rotation of the selector is accomplished by reversing the direction of current flow to the
motor, and this is automatically regulated by
the control unit.
4. The current flow to the electromagnetic clutch
is interrupted if the driver switches OFF the
main switch, or if the operation of the auto
cruise control system is
cancelled as a result of
the input of a cancel signal to the control unit because the stop light switch, clutch pedal posi-
tion switch (for a manual transaxle) or the park/ neutral position switch (for an automatic trans-
axle) is activated.
5. As a result of the interruption of current to the
electromagnetic clutch, the clutch plate is
caused to return from the electromagnetic
clutch side to the ring gear side by the force of
the spring, and therefore the ring gear be-
comes free.
6. When the ring gear becomes free, the plane-
tary pinion becomes free relative to the sungear, and thus the selector is caused, by the
return spring installed to the selector part, to
return to its original position.
Troubleshooting hint
Diagnostic-No.1 1 (automatically cancelled)
ECU terminal voltage
Terminal
NO.Signal ConditionsTerminal voltage
8Transistor for electro-When the cruise-control switch (main switch) is switch-
magnetic clutch coiled ON o
v
9DC motor drive (“PULL”
During acceleration by RESUME switch
side) 12v
DC motor drive (“REL.”
During speed reduction (coasting) by SET switch
side)ov
20DC motor drive (“PULL” During acceleration by RESUME switch
side) o
v
DC motor drive (“REL.”
During speed reduction (coasting) by SET switch
side) 12v
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AUTO-CRUISE CONTROL SYSTEM - Troubleshooting13-345
6-1. CHECKING THE STOP LIGHT SWITCH CIRCUIT
Battery
7Tco
A
9%6
I-
(GO) :
To stop light
NOTENC: ON at all timesNO: OFF at all times
Description of operation
When the brake pedal is depressed during
con-
stant-speed travel, the stop light switch’s (NC
)
contacts for the cruise-control system open, with
the result that the current to the electromagnetic
clutch of the actuator is interrupted, thus
cancell-
ing the constant-speed travel.
At the same time, moreover, the closing of the (NO) contacts for the stop light results in the
Troubleshooting hint sending of the cancel signal to the control unit, so
that the actuator’s electromagnetic clutch current is discontinued within the control unit, thereby
canceling the constant-speed travel.
The flow of current is from the battery to fuse N O.
(15) of the junction block, the stop light switch.
and the control unit.
Diagnostic-No.16 (automatically cancelled)
ECU terminal voltage
Terminal
No
.
SignalConditions
3Stop light switch (load
When the brake pedal is depressed
side)
When the brake pedal is not depressed
11Stop light switch (pow-At all times
, er supply side)
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Termianl voltage 12v
ov
12v

AUTO-CRUISE CONTROL SYSTEM - Troubleshooting13-347
6-3. CHECKING THE CLUTCH PEDAL POSITION SWITCH CIRCUIT
Ignition
switch
Junction block
ECU
NOTENO: OFF at all time
Description of operation If the clutch pedal is depressed during constant-
speed travel, the contacts of the clutch pedal position switch close, with the result that the
cancel signal is sent to the control unit, so that
the current to the electromagnetic clutch of
Troubleshooting hint
Diagnostic-No.16 (automatically cancelled)
ECU temrinal voltage the actuator is discontinued within the control
unit, thereby canceling the constant-speed travel.
The flow of current is to the ignition switch (IGI),
fuse No. (9) of the junction block, the
clutch pedal position switch, and the control unit.
/ Te;z,nal 1Conditions Terminal voltage
Clutch pedal position
switch When the clutch pedal is depressed
When the clutch pedal is not depressed12v
ov
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AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
NOTE
13-351
Auto-cruise control system cannot be set.
This chart is to be used, then, for troubleshooting if it is not
possible to use the on-board diagnostic for checking.
Prepare to conduct input check.
Where codesNo.21,22, 23, 25 and 26,displayed when,with the vehicle stationary,
the input check codes were recalled?Damaged or disconnected wiring of the ECU power-supply cir-
l Damaged or disconnected wiring of the SET or RESUMEswitch (Go to check chart 2 and 3.)l Damaged or disconnected wiring of the stop light switch,clutch pedal position switch or park/neutral position switch (Go
1 Are the results of all input checks normals?
YesNo
ck the auto-cruise vacuum pump circuit.1 (Go to check chart No.5.)
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Check results
’Probable cause RemedyCheck chartNo.
Code 21 remains even though SETswitch is set to OFF. SET switch ON mal-function
SET switch input line
short-circuitF,I~JI;? the control
Repair the harness.
No. 2
Code 22 remains even though RE-SUME switch is set to OFF. RESUME switch ON
Replace the controlNo.3malfunctionswitch.
RESUME switch inputRepair the harness.line short-circuit
Code 23 is not canceled even if theMalfunction of stopReplace stop lightNo.6
stop light switch is turned OFF by light switch circuit.switch or repair har-
releasing the brake pedal.
ness.
Code 25 does not disappear, and
Malfunction of theCheck or repair theNo.4
code 24 does not appear, evenvehicle-speed sensor vehicle speed sensorthough vehicle speed reaches appro-circuit (damaged or dis-circuit.ximately 40 km/h (25 mph) or higher.connected wiring, orshort-circuit)
Code 26 is not canceled even if the Malfunction of clutch
Replace clutch pedalNo.8clutch pedal position switch is turnedpedal position switchposition switch or repairOFF by releasing the clutch pedal.
circuit.harness.
Code 26 is not canceled even if the
Malfunction of park/Replace park/neutralNo. 7
select lever is moved to anything but neutral position ,switchposition switch or repair
v. P .circuit.harness.
NOTE
If the results of the check of the auto-cruise vacuum pump
circuit (check chart No. 5) and of the auto-cruise vacuum pump
and actuator itself
(P.13-401.) reveal no abnormal condition, re-
place the electronic control unit (ECU).

13-352AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
Trouble symptomProbable causeCheck chart No.
Remedy
l The set vehicle speed varies Malfunction of the ve-No.4Repair the vehicle speegreatly upward or downward.hicle speed sensor cir-l “Hunching” (repeated alternatingsensor system, or re-witplace the part.
acceleration and deceleration) oc- curs after setting is made.
Malfunction of the spee-
dometer cable or spee-
dometer drive gear
Auto-cruise vacuum
No.5Repair the auto-cruisepump circuit poor con-vacuum pump or replactactthe part.
Malfunction of the auto-cruise vacuum pump Malfunction of the ECU
-Replace the ECU.
The auto-cruise control system is not Damaged or discon-If the input check code Repair the harness or rezanceled when the brake pedals is netted wiring of the stopNo.23 indicates a mal-
depressed.light switch input circuit; function. No.6place the stop light
switch.
brake switch (for auto-cruise control) malfunc-
tion (short-circuit)
Auto-cruise vacuum
No.5Repair the harness or repump drive circuit short- place the auto-cruise va
circuit.cuum pump.
Malfunction of the ECU
-Replace the ECU.
The auto-cruise control system is not Damaged or discon-If the input check code
Repair the harness, or:anceled when the clutch pedal is netted wiring of clutchNo.26 indicates a mal-repair or replace thedepressed. (vehicles with a manual
pedal position switchfunction. No.8clutch pedal position
ransaxle)input circuitswitch.
It is canceled, however, when theIrake pedal is depressed.) Clutch pedal position
switch improper installa-
tion (won’t switch ON)
Malfunction of the ECU
-Replace the ECU.
*he auto-cruise control system is not Damaged or discon-If the input check code
Repair the harness, or:anceled when the shift lever is netted
wiring of park/No.26 indicates a mal-repair or replace the
noved to the “N” position. (vehicles neutral position switchfunction. No.7park/neutral position
vith an automatic transaxle)input circuit switch.t is canceled, however, when thebrake pedal is depressed.)
Improper adjustment of
park/neutral position
switch
Malfunction of the ECU-Replace the ECU.
anc$ decelerate by using the SET Temporary damaged orNo.2Repair the harness or re-disconnected wiring of
SET switch input circuitplace the SET switch.
Auto-cruise vacuumNo.5Repair the harness or re-pump circuit poor con-
tactplace the auto-cruise va-
cuum pump and actua-
tor.Malfunction of the auto-cruise vacuum pump
and actuator (including
clogging of negative
pressure passage)
Malfunction of the ECU-Replace the ECU.
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