2000 LEXUS GS400 check engine

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.

F04707
F02829
± BRAKEHYDRAULIC BRAKE BOOSTER
BR±45
2153 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(8) Release the MAIN push switch, and check that the
brake pedal can be depressed.
If the pedal cannot be depressed, replace the hydraulic brake
booster.
(9) Release the brake pedal.
(k) Inspect the left front ABS solenoid operation.
(1) Turn the selector switch to ºLHº position.
(2) Push and hold in the MAIN push switch and ºSA1º
switch simultaneously, depress and hold the brake
pedal with stable force.
NOTICE:
Do not keep the MAIN push switch and ºSA1º switch
pushed down for more than 10 seconds. When operating
it continuously, set the interval of more than 20 seconds.
(3) Check that the brake pedal cannot be depressed.
If the pedal can be depressed, replace the hydraulic brake
booster.
(4) Release the MAIN push switch and ºSA1º switch si-
multaneously, and check that the brake pedal can
be depressed.
If the pedal cannot be depressed, replace the hydraulic brake
booster.
(5) Release the brake pedal.
(6) Depress and hold the brake pedal with stable force,
push and hold in MAIN push switch.
NOTICE:
Do not keep the MAIN push switch pushed down for more
than 10 seconds. When operating it continuously, set the
interval of more than 20 seconds.
(7) Check that the brake pedal cannot be depressed.
If the pedal can be depressed, replace the hydraulic brake
booster.
(8) Release the MAIN push switch, and check that the
brake pedal can be depressed.
If the pedal cannot be depressed, replace the hydraulic brake
booster.
(9) Release the brake pedal.
(l) Turn the ignition switch OFF, then reconnect the connec-
tor of sub±wire harness from the one with label of
ºFRONTº to ºREARº.
(m) Place ºSHEET Gº of ºREARº on the actuator checker.
(n) Jack up and support the vehicle.
(o) Start the engine and run it at idle.

F02830
F02831
BR±46
± BRAKEHYDRAULIC BRAKE BOOSTER
2154 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(p) Inspect the rear TRAC & VSC solenoid.
(1) Release the parking brake pedal and shift the shift
lever to ºLº position.
(2) Push and hold the ºSA3º switch and ºSTRº switch
simultaneously.
NOTICE:

Do not keep the ºSTRº switch pushed down for more
than 10 seconds.

Do not keep the ºSA3º switch pushed down for more
than 5 seconds.

When operating it continuously, set the interval of
more than 20 seconds.
(3) Check that the rear wheels stop.
If the rear wheels rotate, replace the hydraulic brake booster.
(4) Release the ºSA3º switch and ºSTRº switch simulta-
neously.
(5) Check that the rear wheels rotate.
If the rear wheels stop, replace the hydraulic brake booster.
(q) Inspect the right rear ABS solenoid.
(1) Turn the selector switch to ºRHº position.
(2) Depress the brake pedal several times and release
the brake pedal when the pump begins rotating.
Wait until the pump stops.
(3) Turn the ignition switch OFF.
(4) Depress the brake pedal with a force of 343 N (35
kgf, 77 lbf), record the fluid surface in the reservoir
tank of the hydraulic brake booster.
(5) Press the MAIN push switch for 10 sec., and check
that the fluid surface in the reservoir tank of the hy-
draulic brake booster does not rise up at this time.
If the fluid surface level rises up, replace the hydraulic brake
booster.
NOTICE:
Do not press MAIN push switch for more than 10 sec. When
operating the switch continuously, do it an interval of more
than 20 seconds.
(6) Start the engine and run it at idle.
(7) Depress the brake pedal.
(8) Release the parking brake pedal and shift the shift
lever to ºLº position.
(9) Once, release the brake pedal. After depressing the
brake pedal with stable force, then push and hold
MAIN push switch.
(10) Check that the right rear wheel rotates.
If the right rear wheel stops, replace the hydraulic brake boost-
er.

F02832
± BRAKEHYDRAULIC BRAKE BOOSTER
BR±47
2155 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(r) Inspect the left rear ABS solenoid.
(1) Turn the selector switch to ºLHº position.
(2) Depress the brake pedal several times and release
the brake pedal when the pump begins rotating.
Wait until the pump stops.
(3) Turn the ignition switch OFF.
(4) Depress the brake pedal with a force of 343 N (35
kgf, 77 lbf), record the fluid surface in the reservoir
tank of the hydraulic brake booster.
(5) Press the MAIN push switch for 10 sec., and check
that the fluid surface in the reservoir tank of the hy-
draulic brake booster does not rise up at this time.
If the fluid surface level rises up, replace the hydraulic brake
booster.
NOTICE:
Do not press MAIN push switch for more than 10 sec. When
operating the switch continuously, do it an interval of more
than 20 seconds.
(6) Start the engine and run it at idle.
(7) Depress the brake pedal.
(8) Release the parking brake pedal and shift the shift
lever to ºLº position.
(9) Once, release the brake pedal. After depressing the
brake pedal with stable force, then push and hold
MAIN push switch.
(10) Check that the left rear wheel rotates.
If the left rear wheel stops, replace the hydraulic brake booster.
(s) Stop the engine and lower the vehicle.
(t) Remove the ºSHEET Gº (SST) and disconnect the actua-
tor checker (SST) and sub±wire harness S (SST) from the
hydraulic brake booster.
(u) Connect the 2 connectors to the actuator.
(v) Clear the DTC (See page DI±389).

F02847
Stop Light Switch
Push Rod
Pedal HeightBR0JB±07
F02849
Pedal Freeplay
± BRAKEBRAKE PEDAL
BR±9
2117 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
BRAKE PEDAL
ON±VEHICLE INSPECTION
1. CHECK PEDAL HEIGHT
Pedal height from asphalt sheet:
150.0 ± 160.0 mm (5.906 ± 6.299 in.)
2. IF NECESSARY, ADJUST PEDAL HEIGHT
(a) Remove the No. 1 under cover, end pad, No. 1 safety pad
and No. 7 heater to register duct (See page BO±88).
(b) Disconnect the connector from the stop light switch.
(c) Loosen the stop light switch lock nut and remove the stop
light switch.
(d) Loosen the push rod lock nut.
(e) Adjust the pedal height by turning the pedal push rod.
(f) Tighten the push rod lock nut.
Torque: 25 N´m (260 kgf´cm, 19 ft´lbf)
(g) Install the stop light switch.
(h) Push in the brake pedal 5 ± 15 mm (0.20 ± 0.59 in.), turn
the stop light switch to lock the nut in the position where
the stop light goes off.
(i) Connect the connector to the stop light switch.
(j) After installation, push in the brake pedal 5 ± 15 mm (0.20
± 0.59 in.), check that stop light lights up.
(k) After adjusting the pedal height, check the pedal freeplay.
(l) Install the No. 7 heater to register duct, No. 1 safety pad,
end pad and No. 1 under cover.
3. CHECK PEDAL FREEPLAY
(a) Stop the engine and depress the brake pedal more than
40 times until there is no more pressure left in the booster.
(b) Push in the pedal by hand until the second point of resis-
tance begins to be felt, then measure the distance, as
shown.
Pedal freeplay: 0.2 ± 2.0 mm (0.008 ± 0.079 in.)
If incorrect, check the stop light switch clearance. If the clear-
ance is OK, then troubleshoot the brake system.
Stop light switch clearance:
0.5 ± 2.4 mm (0.020 ± 0.094 in.)
HINT:
The freeplay to the 1st point of resistance is due to the play be-
tween the clevis and pin. It is 0.2 ± 2.0 mm (0.008 ± 0.079 in.)
on the pedal.

F02850Pedal Reserve Distance BR±10
± BRAKEBRAKE PEDAL
2118 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
4. CHECK PEDAL RESERVE DISTANCE
(a) Remove the floor carpet.
(b) Release the parking brake.
With the engine running, depress the pedal and measure
the pedal reserve distance, as shown.
Pedal reserve distance at 196 N (20 kgf, 44.1 lbf):
More than 93 mm (3.66 in.)
If the reserve distance is incorrect, troubleshoot the brake sys-
tem.

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.