sensor LEXUS GS400 2000 Service Repair Manual

AC0WA±01
I03811
Smog Ventilation
Sensor
No. 2 Cooling Fan Relay
(Marking: FAN NO.2) No. 3 Cooling Fan Relay
(Marking: FAN NO.3)
CompressorMagnetic Clutch Relay
(Marking A/C COMP)
Condenser
Ambient Temperature Sensor Condenser Fan
Engine Coolant Temperature
(ECT) Switch
Air Inlet Servomotor
Blower Motor
Air Outlet Servomotor A/C Amplifier
EvaporatorSolar Sensor A/C Control Assembly
Electrical Multi Vision
(Built in A/C Control Assembly)
Expansion Valve
Air Refiner Filter
Blower Motor Control
Relay Evaporator Temperature
Sensor
Heater Radiator
Air Mix Servomotor
(Driver Side) Air Mix Servomotor
(Passenger Side)Room Temperature
Sensor
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±13
2698 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
LOCATION

I02366
Wire Harness

Packing

Packing
Tube Connector
Evaporator Temperature
Sensor
Bracket Plate
Wire Harness

O±Ring
O±Ring
Tube and Accessory
4.1 (42, 36)
4.1 (42, 36)
Expansion Valve

O±Ring
Evaporator
Plate
Insulator Air Mix Servomotor
(Driver Side)
Air Outlet Servomotor
Air Duct
Cover
Drain PipeDrain Hose Air Mix Servomotor
(Passenger Side)
Heater Radiator
Blower Motor
Control Relay
N´m (kgf´cm, in.´lbf) : Specified torque

Non±reusable part

Packing
Air Duct
± AIR CONDITIONINGAIR CONDITIONING UNIT
AC±23
2708 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

AC0WL±01
AC±26
± AIR CONDITIONINGAIR CONDITIONING UNIT
2711 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DISASSEMBLY
1. REMOVE THESE PARTS:
(a) Wire harness
(b) Drain hose
2. REMOVE HEATER RADIATOR
(a) Remove the screw and clamp.
(b) Pull out the heater radiator.
3. REMOVE BLOWER MOTOR CONTROL RELAY
Remove the screw and blower motor control relay.
4. REMOVE AIR MIX SERVOMOTORS
Remove the 6 screws and both servomotors.
5. REMOVE AIR OUTLET SERVOMOTOR
Remove the 2 screws and servomotor.
6. REMOVE EXPANSION VALVE
(a) Pry out the packing.
HINT:
At the time of reassembly, please refer to the following item.
Do not reuse the packing.
(b) Using SST, remove the 2 bolts, then separate the expansion valve, tube connector and tube and ac-
cessory.
SST 07110±61050
Torque: 4.1N´m (42 kgf´cm, 36 in.´lbf)
HINT:
At the time of reassembly, please refer to the following item.
Lubricate 4 new O±rings with compressor oil and install them to the valve.
7. REMOVE EVAPORATOR TEMPERATURE SENSOR
(a) Disconnect the wire harness clamp.
(b) Using a screwdriver, pull out the sensor with bracket plate.
HINT:
Tape the screwdriver tip before use.
(c) Release the 2 claws and sensor from bracket plate.
8. REMOVE EVAPORATOR
(a) Using SST, remove the 2 bolts and tube and accessory.
SST 07110±61050
Torque: 4.1N´m (42 kgf´cm, 36 in.´lbf)
HINT:
At the time of reassembly, please refer to the following item.
Lubricate 2 new O±rings with compressor oil and install them to the tube.
(b) Remove the 4 screws and cover.
(c) Pull out the evaporator.
(d) Remove the plate from evaporator.
HINT:
At the time of reassembly, please refer to the following item.
If evaporator is replaced, add compressor oil to evaporator.
Add 40 cc (1.4fl.oz.)
Compressor oil: ND±OIL 8 or equivalent
9. REMOVE INSULATOR FROM HEATER CASE
10. REMOVE AIR DUCT
Remove the 4 screws and duct.

± 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.

AC0WT±01
I02373
GS300:
W
1
2
I02374
GS400:
W
1
2
AC±34
± AIR CONDITIONINGCOMPRESSOR AND MAGNETIC CLUTCH
2719 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPRESSOR AND MAGNETIC
CLUTCH
ON±VEHICLE INSPECTION
1. INSPECT COMPRESSOR FOR METALLIC SOUND
Check there is abnormal metallic sound from the compressor
when the A/C switch is ON.
If abnormal metallic sound is heard, replace the compressor as-
sembly.
2. INSPECT REFRIGERANT PRESSURE
(See page AC±3)
3. INSPECT VISUALLY FOR LEAKAGE OF REFRIGER-
ANT
Using a gas leak detector, check for leakage of refrigerant.
If there is any leakage, replace the compressor assembly.
4. INSPECT COMPRESSOR LOCK SENSOR RESIS-
TANCE
(a) Disconnect the connector.
(b) Measure resistance between terminals 1 and 2.
Standard resistance:
570 ± 1,050 W at 20°C (68 °F)
If resistance is not as specified, replace the compressor.

AC0XI±01
AC±70
± AIR CONDITIONINGSERVOMOTOR
2755 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT AIR INLET DAMPER POSITION SENSOR CIRCUIT
(See page DI±1099)
2. INSPECT AIR INLET SERVOMOTOR OPERATION
(See page DI±1111)
3. INSPECT AIR MIX DAMPER POSITION SENSOR CIRCUIT
(See page DI±1096)
4. INSPECT AIR MIX SERVOMOTOR OPERATION
(See page DI±1108)
5. INSPECT AIR OUTLET DAMPER POSITION SENSOR CIRCUIT
(See page DI±1102)
6. INSPECT AIR OUTLET SERVOMOTOR OPERATION
(See page DI±1114)

I03734
AC0XK±01
I03735
Front Side
I03736
AC±72
± AIR CONDITIONINGSENSOR
2757 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SENSOR
REMOVAL
1. REMOVE SOLAR SENSOR
Using a screw driver, pull out the sensor and disconnect the
connector.
HINT:

Tape the screwdriver tip before use.

At the time of installation, please refer to the following
item.
Insert the sensor to instrument panel as shown in the il-
lustration.
2. REMOVE ROOM TEMPERATURE SENSOR
(a) Remove the No. 1 under cover.
(See page BO±91)
(b) Remove the room temperature sensor.
(1) Remove the No.1 safety pad set bolts and screws.
(2) Disconnect the connector and aspirator hose.
(3) Remove the screw and sensor.

I03739
I03737
I03738
I03740
± AIR CONDITIONINGSENSOR
AC±73
2758 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. REMOVE AMBIENT TEMPERATURE SENSOR
(a) Disconnect the connector.
(b) Using a clip remover, pull out the sensor from bumper re-
inforcement.
4. REMOVE EVAPORATOR TEMPERATURE SENSOR
(a) Remove these parts:
(1) No.1 under cover
(2) No.1 safety pad
(See page BO±91)
(b) Remove the evaporator temperature sensor.
(1) Using a screwdriver, pull out the sensor with bracket
plate.
HINT:
Tape the screwdriver tip before use.
(2) Release the 2 claws and remove the sensor from
bracket plate.
5. REMOVE SMOG VENTILATION SENSOR
(a) Disconnect the connector.
(b) Remove the bolt and sensor.

AC0XL±01
AC±74
± AIR CONDITIONINGSENSOR
2759 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT SOLAR SENSOR CIRCUIT
Driver Side: (See page DI±1093)
Passnger Side: (See page DI±1084)
2. INSPECT ROOM TEMPERATURE SENSOR CIRCUIT
(See page DI±1071)
3. INSPECT AMBIENT TEMPERATURE SENSOR CIRCUIT
(See page DI±1074)
4. INSPECT EVAPORATOR TEMPERATURE SENSOR
(See page DI±1078)
5. INSPECT SMOG VENTILATION SENSOR CIRCUIT
(See page DI±1093)

AC0XM±01
± AIR CONDITIONINGSENSOR
AC±75
2760 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
Installation is in the reverse order of removal (See page AC±72).