ECU LEXUS GS400 2000 Service Repair Manual

± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±9
2694 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. INSPECT IDLE±UP SPEED
(a) Warm up engine
(b) Inspect idle±up speed when the these conditions are es-
tablished.
Test conditions:

Blower speed control switch at ºHIº position

Temperature control dial at ºCOOLº position

A/C switch ON

Put gear shift in neutral
GS300:
Magnetic clutch conditionIdle±up speed
Magnetic clutch not engaged700 ± 50 rpm
Magnetic clutch engaged800 ± 50 rpm
If idle speed is not as specified, check the idle control system.
GS400:
Magnetic clutch conditionIdle±up speed
Magnetic clutch not engaged750 ± 50 rpm
Magnetic clutch engaged800 ± 50 rpm
If idle speed is not as specified, check the idle control system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions.

Stop engine

Secure good ventilation (If the gas leak detector
may not react volatile gases which are not refriger-
ant, such as evaporated gasoline and exhaust gas)

Repeat the test 2 or 3 times

Make sure that there is some refrigerant remaining
in the refrigeration system.
When compressor is OFF: approx. 392 ± 588 kPa
(4 ± 6 kgf´cm
2, 57 ± 85 psi)
(b) Bring the gas leak detector close to the drain hose before
performing the test.
HINT:

After the blower motor has stopped, leave the cooling for
more than 15 minutes.

Expose the gas leak detector sensor under the drain
hose.

When bring the gas leak detector close to the drain hose,
make sure that the gas leak detector does not react to the
volatile gases.
If such reaction is unavoidable, the vehicle must be lifted up.
(c) If gas leak is not detected on the drain hose, remove the
blower resistor from the cooling unit. Then insert the gas
leak detector sensor into the unit and perform the test.
(d) Disconnect the connector and leave the pressure switch
for approx. 20 minutes. Then bring the gas leak detector
close to the pressure switch and perform the test.
(e) Bring the gas leak detector close to the refrigerant lines.

AT060±01
D01091
Shift Lock Control ECU Shift Lock Override ButtonKey Interlock Solenoid
Stop Light Switch
± AUTOMATIC TRANSMISSIONSHIFT LOCK SYSTEM
AT±11
1959 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SHIFT LOCK SYSTEM
LOCATION

AT061±01
D01925
ACC
EP1KLS+
SLS+
Z16909
4 (+)
3 (±)
Z16910
4 (+)
3 (±)
AT±12
± AUTOMATIC TRANSMISSIONSHIFT LOCK SYSTEM
1960 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT SHIFT LOCK CONTROL ECU
Using a voltmeter, measure the voltage at each terminal.
HINT:
Do not disconnect the ECU connector.
TerminalMeasuring ConditionSpecified Condition
(1) IG SW ACC and shift lever P position0 V
1 ± 10 (KLS ± E)(2) IG SW ACC and shift lever except P position7.5 ± 11V (about I second)
after 6 ± 9 V
4 10 (ACC E)(1) IG SW ON10 ± 14 V4 ± 10 (ACC ± E)(2) IG SW ACC10 ± 14 V
7 10 (P1 E)(1) Shift lever P position0 V7 ± 10 (P1 ± E)(2) Shift lever except P position10 ± 14 V
(1) IG SW ON and shift lever P position0 V
8 10 (SLSE)(2) IG SW ON and depress brake pedal or shift lever N position3 ± 6 V8 ± 10 (SLS ± E)(3) IG SW ON and release brake pedal or shift lever except P position0 V
(4) IG SW ACC and shift lever except P position3 ± 6 V
10 ± Ground (E ± Ground)ConstantContinuity
2. INSPECT KEY INTERLOCK SOLENOID
(a) Disconnect the solenoid connector.
(b) Using an ohmmeter, measure the resistance between ter-
minals 3 and 4.
Standard resistance: 12 ± 17 W
If the resistance value is not as specified, replace the solenoid.
(c) Touch the solenoid with your finger and check that the so-
lenoid operation can be felt when battery voltage is ap-
plied intermittently to terminals 3 and 4.
If the operation is not as specified, replace the solenoid.

AT063±01
D01039
AT±16
± AUTOMATIC TRANSMISSIONFLOOR SHIFT ASSEMBLY
1964 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. RAISE VEHICLE
NOTICE:
Make sure that the vehicle is securely supported.
2. REMOVE FRONT EXHAUST PIPE
1UZ±FE Engine: (See page EM±120)
2JZ±GE Engine: (See page EM±97)
3. REMOVE HEAT INSULATOR
Remove the 6 bolts and heat insulator.
Torque: 5.4 N´m (55 kgf´cm, 48 in.´lbf)
4. DISCONNECT SHIFT CONTROL ROD
(See page AT±28)
5. LOWER VEHICLE
6. REMOVE THESE PARTS:
(See page BO±88)

Grove compartment panel assembly

Box plate

No.2 under cover

No.1 safety pad

No.1 under cover

Cluster finish panel

Lower rear console box

Console box and rear console armrest

No.3 console box mounting bracket

Ash receptacle

No.1 console box duct

Finish plate

End pad
7. REMOVE SHIFT LEVER ASSEMBLY
(a) Disconnect the connectors and wire harness from the
shift lever assembly.
(b) Remove the 4 bolts and shift lever assembly.
Torque: 8.3 N´m (85 kgf´cm, 74 in.´lbf)

AT065±01
D01085
D01084
Lip
D01083
D01082
AT±22
± AUTOMATIC TRANSMISSIONFLOOR SHIFT ASSEMBLY
1970 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REASSEMBLY
HINT:
Before reassembly, apply MP grease to the parts indicated by
arrows.
(See page AT±13)
1. INSTALL CLIP, CONNECTING ROD SWIVEL, LOWER
CONTROL SHAFT BUSHING, LOWER CONTROL
SHAFT PIECE, PLATE WASHER AND SHIFT LEVER
BOOT TO CONTROL LEVER
(a) Install the shift lever boot, 2 plate washers, lower control
shaft piece, lower control shaft bushing and connecting
rod swivel to the control lever.
(b) Using pliers, install the clip.
2. INSTALL CONTROL LEVER, SPACER AND CONTROL
SHAFT
(a) Connect the shift lever boot to the shift lever plate.
HINT:
Pull out the 3 lips of the shift lever boot securely, as shown in
the illustration.
(b) Install the control shaft and 2 spacers.
(c) Install and torque the nut.
Torque: 13 N´m (128 kgf´cm, 9 ft´lbf)
3. INSTALL SHIFT LEVER SUB±ASSEMBLY
(a) Install a new shift lever nut to the shift lever sub±assem-
bly.
HINT:
Insert the shift lever nut securely until it fits and check there is
no looseness.

D01066
D01065
D01064
D01062
D01924
± AUTOMATIC TRANSMISSIONFLOOR SHIFT ASSEMBLY
AT±25
1973 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(c) Connect the indicator lamp wire sub±assembly to the shift
lever plate.
HINT:
Hook the indicator lamp wire sub±assembly securely on the re-
tainer of the shift lock plate.
12. INSTALL SHIFT LOCK RELEASE LINK AND SPRING
(a) Install the shift lock release spring to the shift lock release
link.
(b) Install the 2 shift lever housing set bolts, nuts, shift lock
release link and spring.
(c) Torque the 2 nuts.
Torque: 3.9 N´m (40 kgf´cm, 35 in.´lbf)
13. INSTALL SLIDE COVER
14. INSTALL POSITION INDICATOR LENS TO POSITION
INDICATOR HOUSING
HINT:
Fit the 4 claws of the position indicator lens in the grooves of the
position indicator housing securely.
15. INSTALL POSITION INDICATOR HOUSING
(a) Install the shift lever cap to the position indicator housing.
(b) Install the position indicator housing to the shift lever
plate.
HINT:
Fit the 4 clips of the position indicator housing in the shift lever
plate securely.
16. INSTALL WIRE PROTECTOR TO SHIFT LEVER PLATE
17. INSTALL SHIFT LEVER KNOB AND SHIFT LEVER
KNOB COVER

AT068±01
D01041
D01042
AT±28
± AUTOMATIC TRANSMISSIONAUTOMATIC TRANSMISSION UNIT (2JZ±GE)
1976 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. REMOVE LEVEL GAUGE
2. REMOVE FILLER PIPE
Remove the bolt and filler pipe with the O±ring.
HINT:
At the time of installation, please refer to the following item.
Replace the used O±ring with a new one.
3. REMOVE AIR CLEANER, MAF METER AND INTAKE
AIR CONNECTOR PIPE ASSEMBLY
4. REMOVE EXHAUST MANIFOLD WITH TWC
Remove the 8 nuts, 2 gaskets and exhaust manifold with the
TWC.
Torque: 39 N´m (400 kgf´cm, 29 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
Replace the used gaskets with new ones.
5. RAISE VEHICLE
NOTICE:
Make sure that the vehicle is securely supported.
6. REMOVE ENGINE UNDER COVER
7. REMOVE FRONT AND CENTER EXHAUST PIPE
(a) Disconnect the heated oxygen sensor.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
HINT:
At the time of installation, please refer to the following items.

Before installing the heated oxygen sensor, twist the sen-
sor wire counterclockwise 3 and 1/2 turns.

After installing the heated oxygen sensor wire should not
twist. If it is twisted, remove the heated oxygen sensor
and reinstall it.
(b) Remove the 2 bolts and front floor center brace.
Torque: 7.4 N´m (75 kgf´cm, 65 in.´lbf)
(c) Remove the 3 bolts, nuts and 2 gaskets.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
Replace the used nuts and gaskets with new ones.
(d) Remove the 2 bolts and pipe support bracket.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)

AT06B±01
D01050
D01051
D00999
AT±34
± AUTOMATIC TRANSMISSIONAUTOMATIC TRANSMISSION UNIT (1UZ±FE)
1982 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. REMOVE LEVEL GAUGE
2. RAISE VEHICLE
NOTICE:
Make sure that the vehicle is securely supported.
3. REMOVE ENGINE UNDER COVER
4. REMOVE FRONT AND CENTER EXHAUST PIPES
(a) Disconnect he 2 heated oxygen sensor.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
HINT:
At the time of installation, please refer to the following items.

Before installing the heated oxygen sensor, twist the sen-
sor wire counterclockwise 3 and 1/2 turns.

After installing the heated oxygen sensor wire should not
twist. If it is twisted, remove the heated oxygen sensor
and reinstall it.
(b) Remove the 2 bolts and front floor center brace.
Torque: 7.4 N´m (75 kgf´cm, 65 in.´lbf)
(c) Remove the 4 bolts, nuts and 2 gaskets from the LH and
RH front TWC.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
Replace the used nuts and gaskets with new ones.
(d) Remove the 2 bolts and support bracket.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
(e) Remove the 4 bolts and 2 gaskets from the tail pipe.
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
Replace the used gaskets with new ones.
(f) Disconnect the front and center exhaust pipes from the 2
O±rings and remove them.
5. REMOVE LH AND RH FRONT TWC
Remove the 6 nuts, 2 gaskets, LH and RH front TWC.
Torque: 62 N´m (630 kgf´cm, 46 ft´lbf)
HINT:
At the time of installation, please refer to the following item.
Replace the used nuts and gaskets with new ones.

BE01I±09
± BODY ELECTRICALBODY ELECTRICAL SYSTEM
BE±1
2302 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
BODY ELECTRICAL SYSTEM
PRECAUTION
HINT:
Take care to observe the following precautions when performing inspections or removal and replacement
of body electrical related parts.
1. HEADLIGHT SYSTEM

Halogen bulbs have pressurized gas inside and require special handling. They can burst if scratched
or dropped. Hold a bulb only by its plastic or metal case. Don't touch the glass part of a bulb with bare
hands.

When high voltage socket of discharge headlight is touched with the light control switch HEAD, high
voltage of 20,000 V is momentarily generated. This might lead to a serious accident.

Never connect the tester to the high voltage socket of discharge headlight for measurement, as this
leads to a serious accident because of high voltage.

When performing operation related to the discharge headlight, make sure to do it in the place with no
water of rain to prevent electric shock, with light control switch OFF, battery terminal removed, connec-
tor of light control ECU disconnected.

When performing operation related to the discharge headlight, make sure to do it after assembling has
been completely over and never light up without a bulb installed.

Do not light up the discharge headlight using another power source except vehicle's.

When there is a defect on the discharge headlight or any shock has been applied to it, replace the light
with a new one.
Even if the light operates normally, there is a possibility that the fail±safe function works.
2. SRS (SUPPLEMENTAL RESTRAINT SYSTEM)
The LEXUS GS300/ 400 is equipped with an SRS (Supplemental Restraint System) such as the driver airbag
and front passenger airbag. Failure to carry out service operation in the correct sequence could cause the
SRS to unexpectedly deploy during servicing, possibly leading to a serious accident. Before servicing (in-
cluding removal or installation of parts, inspection or replacement), be sure to read the precautionary notices
in the RS section.
3. COMBINATION METER SYSTEM
The cold cathode tube connectors (Connector ºKºand ºLº) in the combination meter are charged with high
voltage AC current when power is supplied, so do not touch them when they are charged.

BE0GU±05
I01361
Ignition Switch
Buckle Switch
Driver Side Junction Block

ECU±IG Fuse
Electric Tension Reducer Solenoid
BE±104
± BODY ELECTRICALELECTRIC TENSION REDUCER SYSTEM
2405 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC TENSION REDUCER SYSTEM
LOCATION