1991 MITSUBISHI 3000GT clutch

23-20AUTOMATIC TRANSAXLE - Troubleshootina
TROUBLESHOOTING GUIDE
‘resumed cause
38Malfunction of transaxle control unttX
NOTE- @ indicates items of prlortty during Inspection.PSCV = Pressure control solenoid valveAbbrewatlons TPS = Throttle powon sensor
DCCSV = Damper clutch control solenoid valveSCSV = Shift control solenoid valveOD = Overdwe
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23-22AUTOMATIC TRANSAXLE - Troubleshooting
0”
TM362
DIAGNOSIS AND TEST
FLUID LEVEL AND CONDITION
1.Drive until the fluid temperature reaches the usual tempera-
ture
[70 - 80°C (160 - 18O”F)].2. Place vehicle on level floor.
3. Move selector lever sequentially to every position to fill
torque converter and hydraulic circuit with fluid, then place
lever in “N” Neutral position. This operation is necessary to
be sure that fluid level check is accurate.
4. Before removing dipstick, wipe all dirt from area around
dipstick. Then take out the dipstick and check the condition
of the fluid.
The transaxle should be overhauled under the following
conditions.
l If there is a “burning” odor.
l If the fluid color has become noticeably blacker.
lIf there is a noticeably great amount of metal particles in
the fluid.
5.Check to see if fluid level is in “HOT” range on dipstick. If
fluid level is low, add automatic transaxle fluid until level
reaches “HOT” range.
Low fluid level can cause a variety of conditions because it
allows pump to take in air along with fluid. Air trapped in
hydraulic circuit forms bubbles which make fluid spongy.
Therefore, pressures will be erratic.
Improper filling can also raise fluid level too high. When
transaxle has too much fluid, gears churn up foam and
cause same conditions which occur with low fluid level,
resulting in accelerated deterioration of automatic transaxle
fluid.
dIn either case, air bubbles can cause overheating, fluid
oxidation, which can interfere with normal valve, clutch, and
servo operation. Foaming can also result in fluid escaping
from transaxle vent where it may be mistaken for a leak.
6. Be sure to examine fluid on dipstick closely.
,CONTROL CABLEWhether control cable is properly adjusted can be confirmed by
checking whether inhibitor switch is performing well.
1. Apply parking brakes and service brakes securely.
2. Place selector lever to “R” range.
3. Set ignition key to “ST” position.
4. Slowly move the selector lever upward until it clicks as it
fits in notch of “P” range. If starter motor operates when
lever makes a click, “P” position is correct.
5.Then slowly move selector lever to “N” range by the same
procedure as in foregoing paragraph. If starter motor
operates when selector lever fits in
“N”, “N” position is
correct.
6. Also check to be sure the vehicle doesn’t begin to move
and the lever doesn’t stop between P-R-N-D.
7. The control cable is properly adjusted if, as described
above, the starter motor starts at both the “P” range and
the “N” range.
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AUTOMATIC TRANSAXLE - Troubleshooting23-25
L
L
ZodeNo.
31Display Pattern
ItemRemedial Action
Open-circuited pulse generator Al Check pulse generator A or B on
bench.
32l Check vehicle-speed reed switch
(chattering).
Open-circuited pulse generator B
Open-circuited shift control
solenoid valve Al Check solenoid valve connector.
l Check shift control solenoid valve
A on bench.
42Short-circuited shift control
solenoid valve A
Open-circuited shift control
solenoid valve Bl Check solenoid valve connector.
l Check shift control solenoid valve
B on bench.
Short-circuited shift control
solenoid valve B
45
uuuLNulM-Open-circuited pressure controll Check solenoid valve connector.
solenoid valvel Check pressure control solenoid
valve on bench.
46Short-circuited pressure
control solenoid valve
Open-circuited damper clutch
control solenoid valvel Check solenoid valve connector.
l Check damper clutch control
solenoid valve on bench.
Short-circuited damper clutch
control solenoid valve
49Defective damper clutch systeml Check damper clutch hydraulic
circuit.
lllJl!-l Check damper clutch control
solenoid valve on bench.0 Replace control unit.
12A010712A0105
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23-26AUTOMATIC TRANSAXLE - Troubleshooting
Code
No.Display PatternItemRemedial Action
1 st speed shift not finishl Check connectors of pulse
generators A and
B.l Check pulse generators A and B on
bench.
l Rear clutch slipping
52
uuuuu-ln-2nd speed shift not finishl Check connectors of pulse
generators A and B.
l Check pulse generators A and B on
bench.
l Rear clutch slipping
533rd speed shift not finishl Kickdown brake slipping
l Check connectors of pulse
generators A and B.
4th speed shift not finishl Check pulse generators A and B on
bench.
l Front clutch slipping
l Rear clutch slipping
l Check connectors of pulse
generators A and B.
l Check pulse generators A and B on
bench.
l End clutch slipping
6162l Kickdown brake slipping
Short-circuited torque
reduction request signal linel Check torque reduction request
or open-circuited torquesignal line.
reduction execution signal linel Check torque reduction execution
signal line.
Open-circuited torque reduction
request signal line0 Check torque reduction request
signal line.
63Short-circuited torque
reduction execution signal linel Check torque reduction execution
signal line.
12A0106
‘J
\J
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AUTOMATIC TRANSAXLE - Troubleshootina23-29
Check Iteml
Defective pulse generator B
shielded wire
l External noise interference
l Data listl Item No. 36
l Data listl Item No. 38output where vehicleisstationary.l Otherwise, vehicle-speed reed switch
or circuit harness is defective.
Damper clutchslipl Data listl Item No. 47
DCCSV duty
l Data listl Item No. 49D range, 3rd speed, 1,500 rpm(tachometer reading)
D range, 3rd speed, 3,500 rpm(tachometer reading)
D range, 3rd speed, 1,500 rpm(tachometer reading)
D range, 3rd speed, 3,500 rpm(tachometer reading)
100 - 300 rpm
0 rpm
0%
Depends on loads
l Defective damper clutchl Defective ignition signal line or
pulse generator B circuit
l Incorrect transmission fluid pressurel Defective DCCSV
l Defective TCUl Defective TPS circuitlDefective pulse generator B circuit
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23-30AUTOMATIC TRANSAXLE - Troubleshooting
TRANSMISSION CONTROL UNIT
The connector has 42 pins to accommodate the increased number of senso.r inputs.
Here are the pin assignments.
uu
101.102.103.
104.105.
106.
107.
108.
109.
110.
1.
3':4.
Z:
i:9.10.11.
12.
13.
14.
15.
16.
17.
18.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.Damper clutch control solenoid valve
Shift control solenoid valve A
-Power source
Ground
Pressure control solenoid valve
Shift control solenoid valve B
. .
*Engine communrcatron srgnaiPower source
Ground
Ground
-Accelerator switch
-Diagnosis output terminal
Air-conditioner relay signal
Engine communication signal
Diagnosis control terminal
Engine communication signal
Power source (backup)Kickdown servo switch
Idle switch
oil temperature sensor (Low temperature side)
Oil temperature sensor (High temperature side)
Throttle position sensor
Sensor ground
Vehicle-speed reed switch
Inhibitor switch
(P)Inhibitor switch (R)Inhibitor switch (N)Inhibitor switch (D)
Inhibitor switch (2)
Inhibitor switch
(L)Overdrive switch
Pulse generator B
Pulse generator B
Pulse generator A
Pulse generator A
Ground
Ignition pulse
Power mode signal
TFA0360
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AUTOMATIC TRANSAXLE - Troubleshooting
ELEMENT IN USE AT EACH POSITION OF SELECTOR LEVER
23-31NOTE
/
LCl Front clutch
C2 . Rear clutch
C3 End clutch
Bl . . . Low reverse brake
B2 . . Kickdown brake
OWC One way clutch
SHIFT PATTERNSTwo shift patterns are pre-stored in the control unit of this
transaxle. One is the power pattern (for more powerful
performance), and the other is the economy pattern (for
improved fuel consumption and quieter operation).
The driver can select and switch to the desired pattern by using
the power/economy select switch on the center
Iconsole.The solid lines shown in these shift patterns indicate up-shifts,
and the broken lines indicate down-shifts. The reason why
there is a difference between the shift points for upshifts and
for down-shifts is so that up-shifts and down-shifts will not
occur frequently when driving at a speed in the vicinity of the
shift point.
When the vehicle is stopped, there is a shift to 2nd gear in
order to obtain a suitable “creeping”, but when the accelerator
pedal is then depressed the vehicle starts off in 1st gear.
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AUTOMATIC TRANSAXLE - Troubleshooting
~I+~Pull the parking brake to
set it securely.
I
23-35With the engine idling, de-
press the foot brake firmly.
.
Set the selector
‘3” or “D” range.Stop theengine.Let the engine continue idling.
c .
INormalI
Improper adjustmentof idling
-Readjust1
Replace the damperclutch control
solenoid valve.
1 9$4nFv;itheclutch 1
1 f;w$aul the valve 1
Sticking (seizure) ofthe damDer clutch
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