1991 MITSUBISHI 3000GT air condition

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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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 - Troubleshooting23-39
//!’ 6Rear@FrontclutchpressureI
@Kickdown brakeoressure (Release)
e
OIL PRESSURE TESTS1. Completely warm up the transaxle.
2.Raise the vehicle by using a jack so that the front wheels
can be rotated.
3. Connect an engine tachometer and place it in a position
where it’s easy to see.
4. Attach the special oil-pressure gauge (MD998330-01) and
the adaptor (MD998332-01) to each oil-pressure outlet port.
When the reverse pressure is to be tested, the 3,000
kPa(400 psi) type of gauge should be used.
5. Measure the oil pressure under various conditions, and
check to be sure that the measured results are within the
standard value range shown in the “Standard oil pressure
table” below.
If the oil pressure is not within the specified range, check
and repair as described in the section “Remedial steps if oil
pressure is not normal” on the next page.
STANDARD OIL PRESSURE TABLECondtttonsStandard
011 pressurekPa (PSI)No
SelectEngme
Red&g@000E%00leverspeedGearK/D brakeWD brakeFrontRearLow-TorqueposItlollvposltlon
pressurepressurepressureclutchclutchclutchreverseconverter
(application)(release)
pressurepressurepressurebrakepressure
pressure
1Nldlmg
Neutral
360 - 4808,(51 - 6812
Dldlmg
2nd
360
- 480100-210
730 -830k(51 - 68)
(14-30)
(104 -118)
3(SWFON,
Approx.
4th
360 480
830
-900
830
900
450-650
2,500(51 - 68) (118 128)(118 128)(64 92)
(SWZFF)Approx.
3rd
360 - 480
830
900830 -900 830 - 900
830 -900830
900
450-4
650-2.500(51 - 68)
(118
128)(118 -128) (118 - 128)
(118
128)(118128)
(64-921
52
Approx.
2nd
360
- 480
830--900
830 -900
450
650
2,500
(51 - 68)
(118-128)
(118 -128)
(64-921
Approx
1 st360 480
830 -900
300-450A1.000(51 - 68)
(118 -128)I43 .-64)
Approx.
Reverse
360 480
1.6402.2401.640 2.2401.640 -2.240450-6502.500(51 - 68)(233 - 319) (233 319)(233 319)(64 ~- 921
Approx.
Reverse
360
- 4801.500(213) 1.500 (213)1.500(213)
450~-650
1,000(51 - 68)or moreor moreor more(64 - 92)NOTE
(I)
-: Indicates pressure is below 10 kPa (1.4 psi).
(2)SW-ON: OD switch in ON position.
(3)SW-OFF: OD switch in OFF position.
(4)
a: Pressure IS not standard.
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23-46AUTOMATIC TRANSAXLE - Service Adjustment Procedures
Fluid level must be
within this range.
TFA038:
SERVICE ADJUSTMENT PROCEDURE!5
MZ3FElBJ
TRANSMISSION FLUID LEVEL INSPECTION
1.Drive until the fluid temperature reaches the usual tempera-
ture
170 - 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.
4. Before removing dipstick, wipe all dirt from area
arouniddipstick. 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 transmission fluid until level
reaches “HOT” range.
Transmission fluid: MITSUBISHI PLUS ATF/Automatictransmission fluid “DEXRON”
abr“DEXRON II”
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, causing delayed shift,
slippy clutch and brakes, etc.
Improper filling can also raise fluid level too high. When
transaxle has too much fluid, gears churn up foam
anldcause the same conditions which occur with low fluid level,
resulting in accelerated deterioration of automatic
transaxllefluid.
In 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.
TRANSMISSION FLUID REPLACEMENTM23FCBHRefer to GROUP 00
- Maintenance Service.
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35-16SERVICE BRAKES -Anti-lock Braking System Troubleshooting
BABS warning light stays on when the ignition key is in the “ON” position.
[Explanation]
[Hint]
This is the symptom when the ABS ECU does not
Check the diagnosis output and if there is no output
power up due to broken ECU power circuit, etc.,
voltage or if the MUT and ABS ECU cannot
when the fail safe function operates and isolates thecommunicate, there is a good possibility that power
system or when the warning light drive circuit is
is not flowing to the ECU.
short circuited.
!8IGNIISWIT(-
:Et
J’B @
C151
:
E
COMBINATION
METER
-19
7
------____-_---1
2
610 2
~;@lizEFgIIc,
6227J
r bL-1
IN(IGl)
1
,
ig
)
158
7
r-TSB iCaution
lIf the trouble code is output, the system can
be in the fail safe mode. in such a case, erase
the trouble code and then restart the engine
to check if the system is currently in a fault
condition.
~~~~
~~~~1
I,No ,I
Yes6
Replace ECU.
41,No rIDoes the ABS warning light
remain illuminated even with
the HU connector discon-
nected?
Yes
Short-circuit in harness
between HU or ECU and ABS
warning light
> Repair harness or replace
combination meter.
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35-24SERVICE BRAKES -Anti-lock Braking System Troubleshooting
E-5When diagnosis code “51 VALVE RELAY” is displayed
[Explanation]
When the ignition switch is turned ON, the ABS
ECU switches the valve relay OFF and ON for an
initial check, compares the voltage of the signal to
the valve relay and valve power monitor line voltage
to check whether the valve relay operation isnormal. In addition, normally it monitors whether or
not there is power in the valve power monitor line
since the valve relay is normally ON. Then, if the
supply of power to the valve power monitor line is
interrupted, this trouble code will be output.
EPfiiB EenIGNITIONSWITCH(IG1)
COMSINATIONm
I
H” g@J$s2
4:u
,,8I. -----I/IL’ /
IIII
I /IIII/I/-,----__--_,>yo “-a-‘+G ------------------ ?$”:
;’m[1?610 2pEl%zq~,___ ____________~_______~~~~
>;?
$-:dL1:27 =Yi62.G 22 +%!
i.-I
1/2131a)5161718(QIIO(I ~~~2(13~~a~i5~~6/i7~~~IQ$O~Y~2~3~24~~6~~~28~~~1~2~3~4~5~Remove and check the valve relay.
IWhen the valve relay is checked, are
the following conditions found?
No. 85
-No. 86: Resistance
value 60 - 120 fiNo. 30-No. 87a: Continuity
No. 30 - No. 87: No continuity
When battery voltage is applied
between terminals No. 86 and No. 85.
No. 30
- No. 87: Continuity
No. 30 - No. 87a: No continuity
Yes
Install the valve relay and remove
the HU connector.
E+GG-pqReplace valve relay.
&I/ NnIIWith the ignition key “ON”, does the
Is there continuity between HU No. 8
and No. 7 terminals?
IYes
Connect the HU harness and remove
the ECU connector.Faulty harness in HU
1Does resistance between body con-
nector terminal No. 2 and terminal
No. 27 indicate 60
- 120 II
NoMalfunction of harness
between HU and ECU.
Yes
With the ignition key “ON”, does the
voltage between terminal No. 22 and
ground indicate battery voltage?
YesNo
II- Malfunction of harness
between HU and ABS
ECU.Repair harness.
vision

37A-10STEERING - Service Adjustment Procedures
BLEEDINGM37FKAl
1.Jack up the front wheels and support them by using a floor
stand.
2. Manually turn the oil pump pulley a few times.
3. Turn the steering wheel all the way to the left and to the
right several times.
4. Disconnect the high-tension cable, and then, while operat-
ing the starting motor intermittently, turn the steering
wheel all the way to the left and right several times (for 15
to 20 seconds).
Caution1. During air bleeding, replenish the fluid supply so
that the level never falls below the lower position ofthe filter.
2. If air bleeding is done while engine is running, the
air will be broken up and absorbed into the fluid; besure to do the bleeding only while cranking.
5. Connect the ignition cable, and then start the engine
(idling).
6.Turn the steering wheel to the left and right until there are
no air bubbles in the oil reservoir.
7.Confirm that the fluid is not milky, and that the level is up to
the specified position on the level gauge.
8. Confirm that there is very little change in the fluid level
when the steering wheel is turned left and right.
Fluid level change:wlthln 5 mm 1.2 in.)I
9.Check whether or not the change in the fluid level is within
5 mm
(.2 in.) when the engine is stopped and when it is
Irunning.
Caution
While enginerunningWhile enginestopped13UOl1. If the change of the fluid level is 5 mm
I.2 in.) or
more, the air has not been completely bled from thesystem, and thus must be bled completely.
2. If the fluid level rises suddenly after the engine is
stopped, the air has not been completely bled.
3. If air bleeding is not complete, there will be
abnormal noises from the pump and the flow-
control valve, and this condition could cause a
lessening of the life of the pump, etc.
LJ
I
I~
I~
I
LJ ,
I
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STEERING - Service Adjustment Procedures37A-11
Shut-off valve
Pressure gauge(FuW dose)
Temperature
Shut-off valve
OIL PUMP PRESSURE TESTM37FLAl-l
CHECKING THE OIL PUMP RELIEF PRESSURE
1.Disconnect the pressure hose from the oil pump, and then
connect the special tools.
2. Bleed the air, and then turn the steering wheel several
times while the vehicle is not moving so that the tempera-
ture of the fluid rises to approximately 50
- 60°C (122 -
140°F).3. Start the engine and idle it at 1,000
+ 100 rpm.
4. Fully close the shut-off valve of the pressure gauge and
measure the oil pump relief pressure to confirm that it is
within the standard value range.
Standard value: 7.5
- 8.2 MPa (1,067 - 1,166 psi)
Caution
Pressure gauge shut off valve must not remain closedfor more than 10 seconds.
5.If it is not within the standard value, overhaul the oil pump.
6. Remove the special tools, and then tighten the pressure
hose to the specified torque.
7. Bleed the system.
CHECKING THE PRESSURE UNDER NO-LOAD CONDI-
TIONS
1.
2.
3.
4.
5.
6.
7.Disconnect the pressure hose from the oil pump, and then
connect the special tool.
Bleed the air, and then turn the steering wheel several
times while the vehicle is not moving so that the tempera-
ture of the fluid rises to approximately 50
- 60°C (122 -
140°F).Start the engine and idle it at 1,000
+ 100 rpm.
Check whether or not the hydraulic pressure is the standard
value when no-load conditions are created by fully opening
the shut-off valve of the pressure gauge.
Standard value: 0.8
- 1.0 MPa (114 - 142 psi)
Limit: 1.5
MPa (213 psi)
If it is not within the standard value, the probable cause is a
malfunction of the oil line or steering gear box, so check
these parts and repair as necessary.
Remove the special tools, and then tighten the pressure
hose to the specified torque.
Bleed the system.
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