battery LEXUS GS400 2000 Service Repair Manual

I04097
Battery Ignition
SwitchWarning Light
Wire Harness Side
I04098
Wire Harness Side
I04099
BatteryIgnition
SwitchWarning Light
Wire Harness Side BE±100
± BODY ELECTRICALCOMBINATION METER
2401 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
23. INSPECT REAR LIGHTS WARNING LIGHT
(See page DI±841)
(a) Disconnect the connector from the light failure sensor and
ground terminal 3 on the wire harness side connector.
(b) Start the engine, check that the warning light lights up.
If the warning light does not light up, inspect the bulb or wire har-
ness.
24. INSPECT LIGHT FAILURE SENSOR CIRCUIT
Disconnect connector from the light failure sensor and inspect
the connectors on the wire harness side as follows.
Tester connectionConditionSpecified condition
1 ± GroundConstantContinuity *
2 ± GroundConstantContinuity *
6 ± GroundConstantContinuity *
7 ± GroundConstantContinuity *
11 ± GroundConstantContinuity
12 ± GroundConstantContinuity *
5 ± GroundLight control switch OFFNo voltage
5 ± GroundLight control switch in TAIL or HEADBattery positive voltage
8 ± GroundIgnition switch in LOCK or ACCNo voltage
8 ± GroundIgnition switch ONBattery positive voltage
9, 10 ± GroundStop light switch OFFNo voltage
9, 10 ± GroundStop light switch ONBattery positive voltage
*: There is resistance because this circuit is grounded through
the bulb.
If circuit is as specified, replace the relay.
If circuit is not as specified, wiring diagram and inspect the cir-
cuits connected to other parts.
25. INSPECT ENGINE OIL LEVEL WARNING LIGHT
(a) Disconnect the connector from the switch.
(b) Run the engine.
(c) Turn the ignition switch ON, check that the warning light
lights up approximatery 40 seconds later.
If the warning light does not light up, inspect bulb or wire har-
ness.

I04102
ON OFF
I04103
ON OFF
I04104
Wire Harness Side
I01286
BatteryWarning Light
± BODY ELECTRICALCOMBINATION METER
BE±101
2402 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
26. INSPECT ENGINE OIL LEVEL WARNING SENSOR
(a) Check that continuity exists between terminals with the
switch to below 40 °C (104 °F). (Warning switch ON)
(b) Heat the switch to above 60 °C (140 °F) in an oil bath.
(c) Check that there is continuity between terminals with the
switch ON (float up).
(d) Check that there is no continuity between terminals with
the switch OFF (float down).
If operation is not as specified, replace the switch.
27. INSPECT ENGINE OIL LEVEL WARNING SENSOR
CIRCUIT
Disconnect the switch connector and inspect the connector on
wire harness side, as shown.
Tester connectionConditionSpecified condition
2 ± GroundConstantContinuity
If continuity is not as specified, inspect the wire harness or
ground point.
28. INSPECT OPEN DOOR WARNING LIGHT
Disconnect the connector from the door courtesy switch and
ground terminal 1 on the wire harness side, and check that the
warning light lights up.
If the warning light does not light up, inspect the bulb or wire har-
ness.
29. INSPECT DOOR COURTESY SWITCH CONTINUITY
AND CIRCUIT (See page BE±60)

I04105
Dark
(10k W)Bright
(0W)
4
5
I01322
Battery Ignition
SwitchWarning Light
2 1 Wire Harness Side
I01323
1 2 OFF
ON
I01328
Battery Ignition
SwitchWarning Light
2 1 Wire Harness Side
I04107
12
4
OFF
ON BE±102
± BODY ELECTRICALCOMBINATION METER
2403 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
30. INSPECT LIGHT CONTROL RHEOSTAT OPERATION
Gradually, turn the rheostat knob from the bright side to dark
side and check that the resistance decreases from 10 kW to 0
W between terminal 4 and 5. (Rheostat knob turned to clock-
wise)
If operation is not as specified, replace the rheostat light control.
31. INSPECT WINDOW WASHER LEVEL WARNING
LIGHT
(a) Disconnect the connector from the warning switch and
ground terminal on the wire harness side connector.
(b) Engine running and check that the warning light lights up.
If the warning light does not light up, inspect the bulb or wire har-
ness.
32. INSPECT WINDOW WASHER LEVEL WARNING
SWITCH CONTINUITY
(a) Check that no continuity exists between the terminals with
the switch OFF (float up).
(b) Check that continuity exists between the terminals with
the switch ON (float down).
If operation is not as specified, replace the switch or inspect
ground point.
33. INSPECT SEAT BELT WARNING LIGHT
(a) Disconnect the connector from the retractor switch and
ground terminal on the wire harness side connector.
(b) Turn the ignition switch ON and check that the warning
light lights up.
If the warning light does not light up, inspect the bulb or wire har-
ness.
34. INSPECT SEAT BELT BUCKLE SWITCH CONTINUITY
(a) Check that continuity exists between the terminals 1 and
4 on the switch side connector with the switch ON (belt
fastened).
(b) Check that continuity exists between the terminals 2 and
4 on the switch side connector with the switch OFF (belt
unfastened).
If operation is not as specified, replace the switch.

F02911
SST
Effort Gauge
SST
BR0K7±04
BR±38
± BRAKEHYDRAULIC BRAKE BOOSTER
2146 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HYDRAULIC BRAKE BOOSTER
ON±VEHICLE INSPECTION
1. CHECK HYDRAULIC BRAKE BOOSTER FLUID PRES-
SURE CHANGE
(a) Inspect the battery positive voltage.
Battery positive voltage: 10 ± 14 V
(b) Turn the ignition switch OFF, depress the brake pedal
more than 40 times.
(c) Install LSPV gauge (SST) and brake pedal effort gauge,
bleed air.
SST 09709±29018
(d) When booster does not operate.
Depress the brake pedal and check fluid pressure.
At 245 N (25 kgf, 55 lbf):
Front brake pressureRear brake pressure
1,470 kPa (15 kgf/cm2, 213 psi)
or more0 kPa (0 kgf/cm2, 0 psi)
At 343 N (35 kgf, 77 lbf):
Front brake pressureRear brake pressure
2,059 kPa (21 kgf/cm2, 299 psi)
or more0 kPa (0 kgf/cm2, 0 psi)
(e) When booster operates.
(1) Turn the ignition switch ON and wait until the pump
motor has stopped.
(2) Depress the brake pedal and check fluid pressure.
At 49 N (5 kgf, 11 lbf):
Front brake pressureRear brake pressure
794 ± 1,814 kPa
(8.1 ± 18.5 kgf/cm2, 115 ± 263 psi)
961 ± 2,148 kPa
(9.8 ± 21.9 kgf/cm2, 139 ± 311 psi)
At 98 N (10 kgf, 22 lbf):
Front brake pressureRear brake pressure
3,442 ± 5,011 kPa
(35.1 ± 51.1 kgf/cm2, 499 ± 727 psi)
3,923 ± 5,698 kPa
(40 ± 58.1 kgf/cm2, 569 ± 826 psi)
At 147 N (15 kgf, 33 lbf):
Front brake pressureRear brake pressure
5,629 ± 7,845 kPa
(57.4 ± 80 kgf/cm2, 816 ± 1,138 psi)
6,237 ± 8,640 kPa
(63.6 ± 88.1 kgf/cm2, 905 ± 1,253 psi)
At 196 N (20 kgf, 44 lbf):
Front brake pressureRear brake pressure
8,002 ± 10,591 kPa
(81.6 ± 108 kgf/cm2, 1,161± 1,536 psi)
8,718 ± 11,572 kPa
(88.9 ± 118 kgf/cm2, 1,264 ± 1,678 psi)

D01827
± BRAKEHYDRAULIC BRAKE BOOSTER
BR±39
2147 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. IN CASE OF USING LEXUS HAND±HELD TESTER:
INSPECT HYDRAULIC BRAKE BOOSTER OPERA-
TION
(a) Inspect the battery positive voltage.
Battery positive voltage: 10 ± 14 V
(b) Turn the ignition switch OFF, depress the brake pedal
more than 40 times.
(c) Check that the brake pedal becomes heavy to depress.
If the pedal does not become to be heavy to depress, check and
replace the brake line and hydraulic brake booster.
(d) Turn the ignition switch ON, check the pump motor opera-
tion noise.
If the pump motor does not operate, check and replace the wire
harness and pump motor (See page BR±53).
(e) Connect the LEXUS hand±held tester.
(1) Connect the LEXUS hand±held tester to the DLC3.
(2) Turn the ignition switch ON.
(3) Select the ºACTIVE TESTº mode on the LEXUS
hand±held tester.
HINT:

Please refer to the LEXUS hand±held tester operator's
manual for further details.

To protect the solenoids, hand±held tester turns OFF au-
tomatically 2 secs. after every solenoid has been turned
ON.
(f) Inspect the front TRAC & VSC solenoid operation.
(1) Select ºSA1º and ºSA2º on the LEXUS hand±held
tester.
(2) With ºSA1º and ºSA2º turned ON simultaneously
with the LEXUS hand±held tester, depress the
brake pedal with stable force and check that the
pedal cannot be depressed.
HINT:
To protect the solenoids, LEXUS hand±held tester turns OFF
automatically 2 sec. after every solenoid has been turned ON.
If the pedal can be depressed, replace the hydraulic brake
booster.
NOTICE:
When operating it continuously, set the interval of more
than 20 seconds.
(3) Once, release the brake pedal.

F06049
F02821
Hydraulic Brake
BoosterSub±Wire harness S (SST)
FRONT
REAR
AIR BLEEDActuator Checker (SST)
± BRAKEHYDRAULIC BRAKE BOOSTER
BR±43
2151 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. IN CASE OF USING ABS ACTUATOR CHECKER:
INSPECT HYDRAULIC BRAKE BOOSTER OPERA-
TION
(a) Inspect the battery positive voltage.
Battery positive voltage: 10 ± 14 V
(b) Disconnect the 2 connectors from hydraulic brake boost-
er.
(c) Connect the actuator checker (SST) to the hydraulic
brake booster side wire harness via the sub±wire harness
S (SST), as shown in the chart below.
SST 09990±00150, 09990±00480
HINT:
Connect the connector with the label of ºFRONTº attached to
the connector of actuator checker.
(d) Connect the red cable of the checker to the battery posi-
tive (+) terminal and the black cable to the negative (±) ter-
minal.
(e) Place ºSHEET Gº (SST) of ºFRONTº on actuator checker.
SST 09990±00240
(f) Turn the ignition switch OFF, depress the brake pedal
more than 40 times.
(g) Check that the brake pedal becomes heavy to depress.
If the pedal does not become to be heavy to depress, check and
replace the brake line and hydraulic brake booster.
(h) Turn the ignition switch ON, check the pump motor opera-
tion noise.
If the pump motor does not operate, check and replace the wire
harness and pump motor.

BR120±01
F06051
1
2
± BRAKEHYDRAULIC BRAKE BOOSTER
BR±53
2161 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
INSPECT HYDRAULIC BRAKE BOOSTER PUMP MOTOR
OPERATION
(a) Connct the positive (+) lead from the battery to terminal
1 of pump motor, and the negative (±) lead to terminal 2.
(b) Check that the pump motor operation.

CH043±01
B01372
Except Maintenance±Free Battery
B01888
Maintenance±Free BatteryVoltmeter
± CHARGING (2JZ±GE)CHARGING SYSTEM
CH±1
1603 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CHARGING SYSTEM
ON±VEHICLE INSPECTION
CAUTION:

Check that the battery cables are connected to the
correct terminals.

Disconnect the battery cables when the battery is giv-
en a quick charge.

Do not do tests with a high voltage insulation resis-
tance tester.

Never disconnect the battery while the engine is run-
ning.
1. CHECK BATTERY ELECTROLYTE LEVEL
Check the electrolyte quantity of each cell.
Maintenance±Free Battery:
If under the lower level, replace the battery (or add distilled wa-
ter if possible). Check the charging system.
Except Maintenance±Free Battery:
If under the lower level, add distilled water.
2. Except Maintenance±Free Battery:
CHECK BATTERY SPECIFIC GRAVITY
Check the specific gravity of each cell.
Standard specific gravity: 1.25 ± 1.29 at 20°C (68°F)
If the specific gravity is less than specification, charge the bat-
tery.
3. Maintenance±Free Battery:
CHECK BATTERY POSITIVE VOLTAGE
(a) After having driven the vehicle and in the case that 20
minutes have not passed after having stopped the en-
gine, turn the ignition switch ON and turn on the electrical
system (headlight, blower motor, rear defogger etc.) for
60 seconds to remove the surface charge.
(b) Turn the ignition switch OFF and turn off the electrical sys-
tems.
(c) Measure the battery positive voltage between the nega-
tive (±) and positive (+) terminals of the battery.
Standard voltage: 12.5 ± 12.9 V at 20°C (68°F)
If the voltage is less than specification, charge the battery.
4. CHECK BATTERY TERMINALS AND FUSES
(a) Check that the battery terminals are not loose or cor-
roded.
If the terminals are corroded, clean the terminals.
(b) Check the fusible link and fuses for continuity.

Z03473
Ammeter
Battery
VoltmeterGenerator Disconnect Wire
from Terminal B
B01656
Terminal F
± CHARGING (2JZ±GE)CHARGING SYSTEM
CH±3
1605 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
7. CHECK CHARGE WARNING LIGHT CIRCUIT
(a) Warm up the engine and then turn it off.
(b) Turn off all accessories.
(c) Turn the ignition switch ºONº. Check that the charge warn-
ing light is lit.
(d) Start the engine. Check that the light goes off.
If the light does not go off as specified, troubleshoot the charge
light circuit.
8. INSPECT CHARGING CIRCUIT WITHOUT LOAD
HINT:
If a battery/generator tester is available, connect the tester to
the charging circuit as per manufacturer's instructions.
(a) If a tester is not available, connect a voltmeter and amme-
ter to the charging circuit as follows:

Disconnect the wire from terminal B of the genera-
tor, and connect it to the negative (±) probe of the
ammeter.

Connect the positive (+) probe of the ammeter to
terminal B of the generator.

Connect the positive (+) probe of the voltmeter to
terminal B of the generator.

Ground the negative (±) probe of the voltmeter.
(b) Check the charging circuit as follows:
With the engine running from idling to 2,000 rpm, check
the reading on the ammeter and voltmeter.
Standard amperage: 10 A or less
Standard voltage: 13.2 ± 14.8 V
If the voltmeter reading is more than standard voltage, replace
the voltage regulator.
If the voltmeter reading is less than standard voltage, check the
voltage regulator and generator as follows:

With terminal F grounded, start the engine and
check the voltmeter reading of terminal B.

If the voltmeter reading is more than standard volt-
age, replace the voltage regulator.

If the voltmeter reading is less than standard volt-
age, check the generator.
9. INSPECT CHARGING CIRCUIT WITH LOAD
(a) With the engine running at 2,000 rpm, turn on the high
beam headlights and place the heater blower switch at
ºHIº.
(b) Check the reading on the ammeter.
Standard amperage: 30 A or more
If the ammeter reading is less than the standard amperage, re-
pair the generator.
HINT:
If the battery is fully charged, the indication will sometimes be
less than standard amperage.

B01900
CO0AD±03
B00922
ECT
Switch
Connector
B02072
B02073
Ammeter
Battery(+)
(±)
CO±24
± COOLING (2JZ±GE)ELECTRIC COOLING FAN
1562 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC COOLING FAN
ON±VEHICLE INSPECTION
1. CHECK COOLING FAN OPERATION WITH LOW
TEMPERATURE (Below 83°C (181°F))
(a) Turn the ignition switch ON.
(b) Check that the cooling fan stops.
If not, check the cooling fan relay and ECT switch, and check
for a separated connector or severed wire between the cooling
fan relay and ECT switch.
(c) Disconnect the ECT switch connector.
(d) Check that the cooling fan rotates.
If not, check the fuses, radiator fan main relay, cooling fan relay,
cooling fan, and check for a short circuit between the cooling
fan relay and ECT switch.
(e) Reconnect the ECT switch connector.
2. CHECK COOLING FAN OPERATION WITH HIGH
TEMPERATURE (Above 93°C (199°F))
(a) Start the engine, and raise coolant temperature to above
93°C (199°F).
HINT:
Coolant temperature is the detected value by the ECT switch
on the radiator lower tank.
(b) Check that the cooling fan rotates.
If not, replace the ECT switch.
3. INSPECT COOLING FANS
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 8.5 ± 11.5 A at 20°C (68°F)
(d) Reconnect the cooling fan connector.