I01278
I01279
Battery Ignition
SwitchWarning Light
I04095
OFF
ON
I04096
± BODY ELECTRICALCOMBINATION METER
BE±99
2400 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
17. INSPECT LOW OIL PRESSURE SWITCH CONTINUITY
(a) Disconnect the connector from the switch.
(b) Check that continuity exists between terminal and ground
with the engine stopped.
(c) Check that no continuity exists between terminal and
ground with the engine running.
HINT:
Oil pressure should be over 24.5 kPa (0.25 kgf/cm
2, 3.55 psi).
If operation is not as specified, replace the switch.
18. INSPECT BRAKE WARNING LIGHT
(a) Disconnect the connector from the brake fluid warning
switch.
(b) Release the parking brake pedal.
(c) Connect the terminals on the wire harness side of the lev-
el warning switch connector.
(d) Start the engine, check that the warning light lights up.
If the warning light does not light up, test the bulb or wire har-
ness.
19. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CONTINUITY
(a) Remove the reservoir tank cap and strainer.
(b) Disconnect the connector.
(c) Check that no continuity exists between the terminals with
the switch OFF (float up).
(d) Use siphon, etc. to take fluid out of the reservoir tank.
(e) Check that continuity exists between the terminals with
the switch ON (float down)
(f) Pour the fluid back in the reservoir tank.
If operation is not as specified, replace the switch.
20. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CIRCUIT (See page DI±835)
21. INSPECT PARKING BRAKE SWITCH CONTINUITY
(a) Check that continuity exists between the terminal and
switch body with the switch ON (switch pin released).
(b) Check that no continuity exists between the terminal and
switch body with the switch OFF (switch pin pushed in).
If operation is not as specified, replace the switch or inspect
ground point.
22. INSPECT PARKING BRAKE SWITCH CIRCUIT
(See page DI±796)
BR0JC±04
D01827
LEXUS
Hand±held
Tester
DLC3
BR±4
± BRAKEBRAKE FLUID
2112 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
BRAKE FLUID
BLEEDING
HINT:
If any work is done on the brake system or if air in the
brake lines is suspected, bleed the air from the system.
When bleeding, keep the amount of the fluid within the
line of reservoir between Min. and Max.
NOTICE:
Do not let brake fluid remain on painted surfaces.
Wash it off immediately.
With the reservoir cap removed, when depressing the
brake pedal, the fluid will spray.
1. FILL RESERVOIR WITH BRAKE FLUID
Fluid: SAE J1703 or FMVSS NO. 116 DOT3
2. IN CASE OF USING LEXUS HAND±HELD TESTER:
BLEED HYDRAULIC BRAKE BOOSTER
HINT:
If the hydraulic brake booster has been disassembled, discon-
nect the brake line from the hydraulic brake booster or if the res-
ervoir becomes empty, bleed the hydraulic brake booster.
(a) Turn the ignition switch OFF, depress the brake pedal
more than 40 times.
HINT:
When a pressure in power supply system is released, reaction
force becomes heavy and stroke becomes shorter.
(b) Turn the ignition switch ON, check that the pump stops af-
ter approx. 30 to 40 seconds.
NOTICE:
When the pump does not stop, repeat step (a) and (b) again.
(c) With the ignition switch remained ON, depress the brake
pedal more than 20 times.
(d) Observe the procedure in step 4 and bleed the right and
left front brake caliper.
(e) Holding the brake pedal depressed, bleed the right and
left rear brake caliper.
HINT:
It is not necessary to depress the pedal continuously, as brake
fluid flows out by first depressing.
(f) Connect LEXUS hand±held tester.
(1) Turn the ignition switch OFF, connect the LEXUS
hand±held tester to DLC3.
(2) Turn the ignition switch ON, and select ºAIR
BLEEDINGº on the LEXUS hand±held tester.
HINT:
Please refer to the LEXUS hand±held tester operator's manual
for further details.
CO0A7±01
CO1242
Radiator Cap Tester
Radiator Cap
30° or More
B01882
Radiator Cap Tester
± COOLING (2JZ±GE)RADIATOR
CO±15
1553 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ON±VEHICLE INSPECTION
1. REMOVE RADIATOR CAP
Remove the radiator cap from the radiator.
CAUTION:
To avoid the danger of being burned, do not remove the ra-
diator cap while the engine and radiator are still hot, as fluid
and steam can be blown out under pressure.
2. INSPECT RADIATOR CAP
NOTICE:
If the radiator cap has contaminations, always rinse
it with water.
Before using a radiator cap tester, wet the relief valve
and pressure valve with engine coolant or water.
When performing steps (a) and (b) below, keep the
tester at an angle of over 30° above the horizontal.
(a) Using a radiator cap tester, slowly pump the tester and
check that air is coming from the vacuum valve.
Pump speed: 1 push/(3 seconds or more)
NOTICE:
Push the pump at a constant speed.
If air is not coming from the vacuum valve, replace the radiator
cap.
(b) Pump the radiator cap tester, and measure the relief valve
opening pressure.
Pump speed: 1 push within 1 second
NOTICE:
This pump speed is for the first pump only (in order to close
the vacuum valve). After this, the pump speed can be re-
duced.
Standard opening pressure:
93 ± 123 kPa (0.95 ± 1.25 kgf/cm
2, 13.5 ± 17.8 psi)
Minimum opening pressure:
78 kPa (0.8 kgf/cm
2, 11.4 psi)
HINT:
Use the tester's maximum reading as the opening pressure.
If the opening pressure is less than minimum, replace the radia-
tor cap.
3. INSPECT COOLING SYSTEM FOR LEAKS
(a) Fill the radiator with coolant and attach a radiator cap tes-
ter.
(b) Warm up the engine.
(c) Pump it to 118 kPa (1.2 kgf/cm
2, 17.1 psi), and check that
the pressure does not drop.
If the pressure drops, check the hoses, radiator or water pump
for leaks. If no external leaks are found, check the heater core,
cylinder block and head.
4. REINSTALL RADIATOR CAP
B01860
SST
B01871
Tank
Lock
Plate
O±Ring
CO±22
± COOLING (2JZ±GE)RADIATOR
1560 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Install the drain plug.
8. INSTALL RADIATOR CAP
9. INSPECT FOR WATER LEAKS
(a) Tighten the drain plug.
(b) Plug the inlet pipes of the radiator with SST.
SST 09230±01010
(c) Using a radiator cap tester, apply pressure to the radiator.
Test pressure: 177 kPa (1.8 kgf/cm
2, 26 psi)
(d) Submerge the radiator in water.
(e) Inspect for leaks.
HINT:
On radiators with resin tanks, there is a clearance between the
tank and lock plate where a minute amount of air will remain,
giving the appearance of an air leak when the radiator is sub-
merged in water. Therefore, before doing the water leak test,
first swish the radiator around in the water until all air bubbles
disappear.
10. INSTALL NEW PACKINGS
EC0BD±02
B02709
Gasket
Vacuum
Valve Pressure
Valve
B06544
Vacuum
Gauge
B01982
LEXUS Hand±Held Tester
DLC 3
B06548Battery
± EMISSION CONTROL (2JZ±GE)EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM
EC±7
1458 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT LINES AND CONNECTORS
Visually check for loose connections, sharp bends or damage.
2. INSPECT FUEL TANK FILLER PIPE
Visually check for deformation, cracks or fuel leakage.
3. VISUALLY INSPECT FUEL TANK CAP
Check if the cap and/or gasket are deformed or damaged.
If necessary, repair or replace the cap.
4. INSPECT EVAP SYSTEM LINE
(a) Warm up the engine and stop the engine.
Allow the engine to warm up to normal operating tempera-
ture.
(b) Install a vacuum gauge (EVAP control system test equip-
ment vacuum gauge) to the EVAP service port on the
purge line.
(c) LEXUS Hand±Held Tester:
Forced driving of the VSV for the EVAP.
(1) Connect a LEXUS hand±held tester to the DLC3.
(2) Start the engine.
(3) Push the LEXUS hand±held tester main switch ON.
(4) Use the ACTIVE TEST mode on the LEXUS hand±
held tester to operate the VSV for the EVAP.
(d) If you have no LEXUS Hand±Held Tester:
Forced driving of the VSV for the EVAP.
(1) Disconnect the VSV connector for the EVAP.
(2) Connect the positive (+) and negative (±) leads from
the battery to the VSV terminals for the EVAP.
(3) Start the engine.
B06545
B06743Hose ClipperAir Drain Hose
B06546
Pressure
Gauge
Pressure EC±8
± EMISSION CONTROL (2JZ±GE)EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM
1459 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(e) Check the vacuum at idle.
Vacuum:
Maintain at 0.368 ± 19.713 in.Hg (5 ± 268 in.Aq) for over
5 seconds
HINT:
If the vacuum does not change, you can conclude that the hose
connecting the VSV to the service port has come loose or is
blocked, or the VSV is malfunctioning.
(f) LEXUS Hand±Held Tester:
Conclude forced driving of the VSV for the EVAP.
(1) Stop the engine.
(2) Disconnect the LEXUS hand±held tester from the
DLC3.
(g) If you have no LEXUS Hand±Held Tester:
Conclude forced driving of the VSV for the EVAP.
(1) Stop the engine.
(2) Disconnect the positive (+) and negative (±) leads
from the battery from the VSV terminals for the
EVAP.
(3) Connect the VSV connector for the EVAP.
(h) Disconnect the vacuum gauge from the EVAP service
port on the purge line.
(i) Connect a pressure gauge to the EVAP service port on
the purge line.
(j) Check the pressure.
(1) Close off the air drain hose at the marked position
of the canister with a hose clipper or similar instru-
ment.
(2) Add the pressure (13.5 ± 15.5 in.Aq) from the EVAP
service port.
Pressure:
2 minutes after the pressure is added, the gauge
should be over 7.7 ± 8.8 in.Aq.
HINT:
If you can't add pressure, you can conclude that the hose con-
necting the VSVcanisterfuel tank has slipped off or the
VSV is open.
EM0D1±05
A11132
Compression Tester
± ENGINE MECHANICAL (2JZ±GE)COMPRESSION
EM±3
1357 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPRESSION
INSPECTION
HINT:
If there is lack of power, excessive oil consumption or poor fuel
economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE
Allow the engine to warm up to normal operating temperature.
2. REMOVE ENGINE COVER
Remove the 4 nuts and engine cover.
3. DISCONNECT IGNITION COILS AND HIGH±TENSION
CORD SET ASSEMBLY (See page IG±7)
4. REMOVE SPARK PLUGS
5. DISCONNECT INJECTOR CONNECTORS
6. CHECK CYLINDER COMPRESSION
(a) Insert a compression tester into the spark plug hole.
(b) While cranking the engine, measure the compression
pressure.
HINT:
Always use a fully charged battery to obtain engine revolutions
of 250 rpm or more.
(c) Repeat steps (a) through (b) for each cylinder.
NOTICE:
This measurement must be done in as short a time as pos-
sible.
Compression:
1,324 kPa (13.5 kgf/cm
2, 192 psi) or more
Minimum pressure:
1,079 kPa (11.0 kgf/cm
2, 156 psi)
Difference between each cylinder:
98 kPa (1.0 kgf/cm
2, 14 psi) or less
(d) If the cylinder compression in 1 or more cylinders is low,
pour a small amount of engine oil into the cylinder through
the spark plug hole and repeat steps (a) through (b) for
the cylinder with low compression.
If adding oil helps the compression, it is likely that
the piston rings and/or cylinder bore are probably
worn or damaged.
If pressure stays low, a valve may be sticking or
seating improper, or there may be leakage past the
gasket.
FI7187
IN0379
Sensor Side
ECU Side
IN0378
Sensor SideECU Side
IN0380
Sensor SideECU Side
IN0381
Pull Lightly
Looseness of Crimping
IN±32± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
32 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. CONNECTOR HANDLING
When inserting tester probes into a connector, insert them from
the rear of the connector. When necessary, use mini test leads.
For water resistant connectors which cannot be accessed from
behind, take good care not to deform the connector terminals.
3. CONTINUITY CHECK (OPEN CIRCUIT CHECK)
(a) Disconnect the connectors at both ECU and sensor
sides.
(b) Measure the resistance between the applicable terminals
of the connectors.
Resistance: 1 W or less
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
4. RESISTANCE CHECK (SHORT CIRCUIT CHECK)
(a) Disconnect the connectors on both ends.
(b) Measure the resistance between the applicable terminals
of the connectors and body ground. Be sure to carry out
this check on the connectors on both ends.
Resistance: 1 MW or higher
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
5. VISUAL CHECK AND CONTACT PRESSURE CHECK
(a) Disconnect the connectors at both ends.
(b) Check for rust or foreign material, etc. in the terminals of
the connectors.
(c) Check crimped portions for looseness or damage and
check that the terminals are secured in lock portion.
HINT:
The terminals should not come out when pulled lightly from the
back.