1991 LEXUS SC400 oil pan

No.Gauge reading kPa (kgf/cm2, psi)ConditionProbable causeRemedy
Pressure low at both low and high
pressure sides
Pressure too high at both low and
high pressure sides

Insufficient cooling

Bubbles seen in
sight glass

Insufficient cooling

Frost on tubes from
receiver to
unit
Replace receiver
Insufficient refrigerant(1) Check for gas
leakage with gas
leak tester and
repair if
necessary
(2) Add refrigerant
until bubbles
disappear
Refrigerant flow
obstructed by dirt in
receiver
Insufficient coolingInsufficient cooling of
condenser(1). Clean condenser
(2). Check fan motoroperation
(1). Check amount ofrefrigerant
If refrigerant is
overcharged
(2). Recover refrigeran
t
(3). Evacuate air and charge proper
amount of purified
refrigerant
Refrigerant
overcharged
(1). Replace receiver
(2). Check compres- sor oil to see if
dirtyAir present in system

Insufficient cooling

Frost in Large
amount of dew on
piping at low
pressure side Expansion valve
improperly mounted,
heat sensing tube
defective
(Open too wide)(1) Check heat sensing
tube installation
condition
If (1) is normal
(2) Check expansion valve and replace
if defective
(3). Remove air insystem through
repeatedly
evacuating air
NOTICE:
wAlways recover refrigerant before removing the parts in the refrigerant line a\
nd evacuating air.
w Evacuate air and charge proper amount of purified refrigerant after installing th\
e parts in the
refrigerant line.
HINT at 6:
These gauge indication are for when the refrigeration system has been op\
ened and the refrigerant charged
without evacuating air.
±
AIR CONDITIONING SYSTEM TroubleshootingAC±101
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INSTALLATION OF EVAPORATOR
1. INSTALL REMOVAL PARTSInstall the removal parts in reverse order of removal proce-
dure.
HINT:
wThe tightening torque for the bolt used to install the
expansion valve on the evaporator is shown below.
Specified torque: 5.4 N Vm (55 kgf Vcm, 48 ft Vlbf)
w The tightening torque for the bolts used to install the
liquid tube and suction tube to the cooling is shown
below.
Specified torque: 10 N Vm (100 kgf Vcm, 7 ft Vlbf)
w The tightening torque specified for the bolt used to
install the equalizer tube to EPR is shown below.
Specified torque: 25 N Vm (250 kgf Vcm, 18 ft Vlbf)
2. IF EVAPORATOR WAS REPLACED, ADD COMPRESSOR
OIL TO EVAPORATOR
Add 40±50 cc (1.4±1.7 fl.oz)
Compressor oil: ND OIL 6,
SUNISO NO. 5 GS or equivalent
3. EVACUATE AIR IN REFRIGERATION SYSTEM ANDCHARGE WITH REFRIGERANT
Specified amount: 950 + 50 g (33.44 + 1.76 oz)
4. INSPECT FOR LEAKAGE OF REFRIGERANT
Using a gas leak tester, check for leakage of refrigerant.
AC±124
±
AIR CONDITIONING SYSTEM Evaporator
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OKNG
INSPECTION PROCEDURE
1Check No. 4 solenoid valve.
C
OK
P
C
OK
C
OK
C
OK
Check solenoid resistance
1. Jack up the Vehicle
2. Remove the oil pan.
3. Disconnect the connector
Measure resistance between terminals 1 and 2 of sole-
noid connector.
Resistance: 5.1 ± 5.5

Check solenoid operation
Connect positive  lead with an 8±10 W bulb to terminal
1 of solenoid connector and negative  lead to terminal
2, then check the movement of the valve.
Reference
Check the solenoid's operation
1. Prepare a variable power supply.
2. Connect positive lead of the variable power
supply to terminal 1 of solenoid connector and neg-
ative  lead to terminal 2.
3. Check the movement of the valve when the voltage is gradually increased. (A current greater than 1 A
should not be supplied.)
As the voltage is increased, the valve should move slow-
ly in the direction.
4. Check the movement of the valve when the voltage is cut off.
The valve should return in the direction.
Replace No. 4 solenoid valve.
Go to step
.
AT±84±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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OKNG
OKNG
INSPECTION PROCEDURE
1Check No. 1, No. 2 solenoid valves.
C
OK
P
C
P
OK
C
Electrical Check
1. Jack up the vehicle.
2. Remove oil pan.
3. Disconnect solenoid connector.
Measure resistance between solenoid connector and
body ground.
Resistance: 10 ± 16

Connect positive
lead to terminal of solenoid connec-
tor, negative  lead to solenoid body.
The solenoid makes an operating noise.
Mechanical Check
1. Remove the oil pan.
2. Remove the No. 1 and No. 2 solenoid valves.
1. Applying 490 kPa (5 kgf/cm
2, 71 psi) of compressed
air, check that the solenoid valves do not leak air.
2. When battery positive voltage is supplied to the so-
lenoid valves, check that the solenoid valves open.
Replace solenoid valve.
2Check harness and connector between ECM and solenoid (See page IN±33\
).
Repair or replace harness or connector.
Proceed to next circuit inspection shown on ma-
trix chart (See page AT±66). However, when diag.
trouble code 62 or 63 is displayed, check and re-
place ECM.
AT±92±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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OKNG
INSPECTION PROCEDURE
1Check No. 3 solenoid valve.
C
OK
P
C
OK
C
OK
C
OK
Check solenoid resistance
1. Jack up the vehicle.
2. Remove oil pan.
3. Disconnect solenoid connector.
Measure resistance between terminals 1 and 2 of sole-
noid connector.
Resistance: 3.5 ± 3.9

Check solenoid operation
Connect positive  lead with an 8 ± 10 W bulb to termi-
nal 1 of solenoid connector and negative  lead to ter-
minal 2, then check the movement of the valve.
Reference
Check solenoid operation
1. Prepare a variable power supply.
2. Connect positive  lead of the variable power sup-
ply to terminal 1 of solenoid connector and negative
 lead to terminal 2.
3. Check the movement of the valve when the voltage is gradually increased. (A current greater than 1 A
should not be supplied.)
As the voltage is increased, the valve should move
slowly in the direction.
4. Check the movement of the valve when the voltage is cut off.
The valve should return in the direction.
Replace No. 3 solenoid valve.
Go to step
.
AT±96±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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TORQUE SPECIFICATION
AT07F±04\
 \
Part tightened NVm kgf Vcm ft Vlbf\
 
\

\
Engine x Transmission
 

64
 

650
 

47
\
 \
Rear mounting x Body 25 260 19
\
 \
Rear mounting x Extension housing 25 250 18
\
 \
Transmission housing x Transmission case 14 mm (0.55 in.) 34 345 25
\
 \
17 mm (0.67 in.) 57 580 42
\
 \
Extension housing x Transmission case 34 345 25
\
 \
Valve body x Transmission case 10 100 7
\
 \
Oil strainer 10 100 7
\
 \
Oil pan 7.4 75 65 in.
Vlbf\
 \
No.1 vehicle speed sensor 16 160 12\
 
\

\
No.2 vehicle speed sensor 

5.4 

55 

48 in.
Vlbf
\
 \
Solenoid wiring stopper plate 5.4 55 48 in. Vlbf
\
 \
O/D direct clutch speed sensor 5.4 55 48 in. Vlbf
\
 \
Transmission output flange 123 1,250 90
\
 \
Throttle cable x Transmission case 5.4 55 48 in. Vlbf
\
 \
Union 29 300 22
\
 \
Cooler pipe union nut 34 350 25
\
 \
Drive plate x Crankshaft 99 1,000 72
\
 \
Torque converter clutch x Drive plate 33 340 25\
 \
Park/Neutral position switch Bolt 13 130 9\
 \
Nut 6.9 70 61 in. Vlbf\
 
\

\
Control shaft lever
 

16
 

160
 

12
±
A340E (1UZ±FE) AUTOMATIC TRANSMISSION SERVICE SPECIFICATIONSAT±123
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EQUIPMENT
AT06V±05\
 \
Feeler gauge Check major clearance\
 
\

\
Vernier calipers
 

Check length of second coast brake
piston rod.
\
 
\

\
Dial indicator or dial indicator with magnetic baseCheck piston stroke and end play of
the output shaft.
\
 
\

\
Dial indicator with magnetic baseCheck inside diameter of major
bushing.
\
 \
Straight edgeCheck side clearance of oil pump.
\
 \
Torque wrench
\
 
\

\
Cylinder gaugeCheck inside diameter of the trans-
mission case rear bushing.
\
 \
Voltmeter
\
 \
Ammeter(A)
\
 \
Ohmmeter
LUBRICANT
AT0GW±03
 Item Capacity Classification
 Automatic transmission fluid
 Dry fill 8.2 liters (8.7 US qts, 7.2 lmp. qts) ATF Type T±II or equivalent
 Drain and refill 1.9 liters (2.0 US qts, 1.7 lmp. qts) 
SSM (SPECIAL SERVICE MATERIALS)
AT06X±03
\
 \
08826±00090 Seal Packing 1281, Transmission case X Oil pan
\
 
\

\

THREE BOND 128\
1 or equivalentTransmission case X Extension
housing
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION PREPARATIONAT±13
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VALVE BODY
VALVE BODY REMOVAL
AT0GG±02
1. DRAIN ATF
2. REMOVE FRONT EXHAUST PIPE(See pages EG±204)
3. REMOVE OIL PAN
(a) Remove the 19 bolts.
(b) Install the blade of SST between the transmission case and oil pan, cut off applied sealer.
SST 09032±00100
NOTICE: Be careful not to damage the oil pan flange.
4. EXAMINE PARTICLES IN PANRemove the magnets and use them to collect steel particles.
Carefully look at the foreign matter and particles in the pan
and on the magnets to anticipate the type of wear you will find
in the transmission:
Steel (magnetic) 0 bearing, gear and clutch plate wear
Brass (non±magnetic) 0 bushing wear
5. REMOVE OIL STRAINER Remove the 3 bolts holding the oil strainer to the valve body.
6. REMOVE SOLENOID WIRING
(a) Remove the 2 bolts and the clamp.
(b) Disconnect the 4 connectors from the solenoid valves.
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION VALVE BODYAT±19
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