2000 LEXUS GS400 check engine light

F02853
B01549
F02853
IN±18
± INTRODUCTIONFOR ALL OF VEHICLES
18 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. FOR VEHICLES EQUIPPED WITH VEHICLE SKID
CONTROL (VSC) SYSTEM
NOTICE:
When using a 2±wheel drum tester such as a speedometer
tester or chassis dynamometer, etc., or jacking up the rear
wheels and driving the wheels, always push in the TRAC &
VSC cut switch and turn the TRAC & VSC system OFF.
(a) Press the VSC OFF switch.
(b) Check that the VSC OFF indicator light comes ON.
HINT:
The VSC OFF indicator light should be always OFF when the
engine is restarted.
(c) Begin measurements.
(d) Press the VSC OFF switch again to change the TRAC &
VSC system to operational condition and check that the
VSC OFF indicator light goes off.
HINT:
The SLIP indicator light blinks when the TRAC system is opera-
tional.

V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR1
Slightly shake the connector vertically and horizontally.
Slightly shake the wire harness vertically and horizontally.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thorough-
ly.
Apply slight vibration with a finger to the part of the sensor
considered to be the problem cause and check that the mal-
function occurs.Shake Slightly
Swing Slightly
Vibrate Slightly
HINT:
Applying strong vibration to relays may result in open relays.
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±25
25 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. SYMPTOM SIMULATION
The most difficult case in troubleshooting is when there are no problem symptoms occurring. In such cases,
a thorough customer problem analysis must be carried out, then simulate the same or similar conditions and
environment in which the problem occurred in the customer's vehicle. No matter how much experience a
technician has, or how skilled he may be, if he proceeds to troubleshoot without confirming the problem
symptoms he will tend to overlook something important in the repair operation and make a wrong guess
somewhere, which will only lead to a standstill. For example, for a problem which only occurs when the en-
gine is cold, or for a problem which occurs due to vibration caused by the road during driving, etc., the prob-
lem can never be determined so long as the symptoms are confirmed with the engine hot condition or the
vehicle at a standstill. Since vibration, heat or water penetration (moisture) is likely cause for problem which
is difficult to reproduce, the symptom simulation tests introduced here are effective measures in that the ex-
ternal causes are applied to the vehicle in a stopped condition.
Important Points in the Symptom Simulation Test:
In the symptom simulation test, the problem symptoms should of course be confirmed, but the problem area
or parts must also be found out. To do this, narrow down the possible problem circuits according to the symp-
toms before starting this test and connect a tester beforehand. After that, carry out the symptom simulation
test, judging whether the circuit being tested is defective or normal and also confirming the problem symp-
toms at the same time. Refer to the problem symptoms table for each system to narrow down the possible
causes of the symptom.

B02389
B02390
HEAT METHOD: When the problem seems to occur when the suspect area is heated. 2
NOTICE:3 WATER SPRINKLING METHOD:
(1)
(2)
4 OTHER: When a malfunction seems to occur when electrical load is excessive.When the malfunction seems to occur on a rainy day or in a
high±humidity condition. Heat the component that is the likely cause of the malfunction
with a hair dryer or similar object. Check to see if the malfunction
occurs.
Sprinkle water onto the vehicle and check to see if the malfunc-
tion occurs.
Turn on all electrical loads including the heater blower, head
lights, rear window defogger, etc. and check to see if the mal-
function occurs.ON HINT:
If a vehicle is subject to water leakage, the leaked water may
contaminate the ECU. When testing a vehicle with a water leak-
age problem, special caution must be taken.
Malfunc-
tion
Do not heat to more than 60 °C (140 °F). (Temperature
is limited not to damage the components.)
Do not apply heat directly to parts in the ECU. (1)
(2)
Never sprinkle water directly into the engine compart-
ment, but indirectly change the temperature and hu-
midity by applying water spray onto the radiator front
surface.
Never apply water directly onto the electronic compo-
nents. NOTICE: IN±26
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
26 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

MA002±06
MA±2
± MAINTENANCEINSIDE VEHICLE
45 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSIDE VEHICLE
GENERAL MAINTENANCE
These are maintenance and inspection items which are considered to be the owner's responsibility.
They can be done by the owner or they can have them done at a service shop.
These items include those which should be checked on a daily basis, those which, in most cases, do not
require (special) tools and those which are considered to be reasonable for the owner to do.
Items and procedures for general maintenance are as follows.
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.

Failure to do even one item an cause the engine to run poorly and increase exhaust emissions.
2. LIGHTS
(a) Check that the headlights, stop lights, taillights, turn signal lights, and other lights are all working.
(b) Check the headlight aiming.
3. WARNING LIGHTS AND BUZZERS
Check that all warning lights and buzzers function properly.
4. HORN
Check that it is working.
5. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
6. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
7. WINDSHIELD DEFROSTER
Check that air comes out from the defroster outlet when operating the heater or air conditioner.
8. REAR VIEW MIRROR
Check that it is mounted securely.
9. SUN VISORS
Check that they move freely and are mounted securely.
10. STEERING WHEEL
Check that it has the specified freeplay. Be alert for changes in steering condition, such as hard steering,
excessive freeplay or strange noises.
11. SEATS
(a) Check that all front seat controls such as seat adjusters, seatback recliner, etc. operate smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the locks hold securely in any latched position.
(d) Check that the head restraints move up and down smoothly and that the locks hold securely in any
latches position.
(e) For folding±down rear seat backs, check that the latches lock securely.
12. SEAT BELTS
(a) Check that the seat belt system such as the buckles, retractors and anchors operate properly and
smoothly.
(b) Check that the belt webbing is not cut, frayed, worn or dameged.

SF0N1±03
± SFI (2JZ±GE)SFI SYSTEM
SF±1
1467 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SFI SYSTEM
PRECAUTION
1. BEFORE WORKING ON FUEL SYSTEM, DISCON-
NECT NEGATIVE (±) TERMINAL CABLE FROM BAT-
TERY
HINT:
Any diagnostic trouble code retained by the ECM will be erased
when the battery negative (±) terminal cable is removed from
the battery.
Therefore, if necessary, read the diagnostic trouble code(s) be-
fore removing the negative (±) terminal cable from the battery.
2. DO NOT SMOKE OR WORK NEAR AN OPEN FLAME
WHEN WORKING ON FUEL SYSTEM
3. KEEP GASOLINE AWAY FROM RUBBER OR LEATH-
ER PARTS
4. MAINTENANCE PRECAUTIONS
(a) Precaution when the connecting gauge.
Use battery as the power source for the timing light, etc.
(b) In the event of engine misfire, these precautions should
be taken.
(1) Check proper connection of battery terminals, etc.
(2) Handle high±tension cords carefully.
(3) After repair work, check that the ignition coil termi-
nals and all other ignition system lines are recon-
nected securely.
(4) When cleaning the engine compartment, be espe-
cially careful to protect the electrical system from
water.
(c) Precautions when the handling heated oxygen sensors.
(1) Do not allow oxygen sensor to drop or hit against an
object.
(2) Do not allow the sensor to come into contact with
water.
5. IF VEHICLE IS EQUIPPED WITH MOBILE RADIO SYS-
TEM (HAM, CB, ETC.)
If the vehicle is equipped with a mobile communication system,
refer to the precaution in the IN section.
6. AIR INDUCTION SYSTEM
(a) Separation of the engine oil dipstick, oil filler cap, PCV
hose, etc. may cause the engine to run out of tune.
(b) Disconnection, looseness or cracks in the parts of the air
induction system between the throttle body and cylinder
head will cause air suction and cause the engine to run
out of tune.

FI2553
SST
SF±2
± SFI (2JZ±GE)SFI SYSTEM
1468 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
7. ELECTRONIC CONTROL SYSTEM
(a) Before removing SFI wiring connectors, terminals, etc.,
first disconnect the power by either turning the ignition
switch OFF or disconnecting the negative (±) terminal
cable from the battery.
HINT:
Always check the diagnostic trouble code before disconnecting
the negative (±) terminal cable from the battery.
(b) When installing the battery, be especially careful not to in-
correctly connect the positive (+) and negative (±) cable
terminals.
(c) Do not permit parts to receive a severe impact during re-
moval or installation. Handle all SFI parts carefully, espe-
cially the ECM.
(d) Do not be careless during troubleshooting as there are
numerous transistor circuits and even slight terminal con-
tact can further troubles.
(e) Do not open the ECM cover.
(f) When inspecting during rainy weather, take care to pre-
vent entry of water. Also, when washing the engine
compartment, prevent water from getting on the SFI parts
and wiring connectors.
(g) Parts should be replaced as an assembly.
(h) Care is required when pulling out and inserting wiring con-
nectors.
(1) Release the lock and pull out the connector, pulling
on the connectors.
(2) Fully insert the connector and check that it is locked.
(i) When inspecting a connector with a volt/ohmmeter.
(1) Carefully take out the water±proofing rubber if it is
a water±proof type connector.
(2) Insert the test probe into the connector from wiring
side when checking the continuity, amperage or
voltage.
(3) Do not apply unnecessary force to the terminal.
(4) After checking, install the water±proofing rubber on
the connector securely.
(5) Use SST for inspection or test of the injector or its
wiring connector.
SST 09842±30070

SF0ND±04
B01220
New Insulator
New O±Ring
New Grommet New O±Ring
B01571
Turn
Outward
Connector
B01580
RotateUpward SF±24
± SFI (2JZ±GE)INJECTOR
1490 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
1. INSTALL INJECTORS AND DELIVERY PIPE
(a) Install new insulator and grommet to each injector.
(b) Apply a light coat of spindle oil or gasoline to 2 new O±
rings and install them to each injector.
(c) Apply a light coat of spindle oil or gasoline on the place
where a delivery pipe touches an O±ring of the injector.
(d) While turning the injector clockwise and counterclock-
wise, push it to the delivery pipe. Install the 6 injectors.
(e) Position the injector connector outward.
(f) Place the 3 spacers in position on the intake manifold.
(g) Apply a light coat of spindle oil or gasoline on the place
where a intake manifold touches an O±ring of the injector.
(h) Place the 6 injectors together with the delivery pipe and
3 bolts in position on the intake manifold.
(i) Temporarily install the 3 bolts holding the delivery pipe to
the intake manifold.
(j) Check that the injectors rotate smoothly.
HINT:
If injectors do not rotate smoothly, the probable cause is incor-
rect installation of O±rings. Replace the O±rings.
(k) Position the injector connector upward.
(l) Connect the 6 injector connectors.
HINT:
The Nos.1, 3, 5 injector connectors and dark gray, and the
Nos.2, 4, 6 injector connectors are brown.
(m) Tighten the 3 bolts holding the delivery pipe to the intake
manifold.
Torque: 21 N´m (210 kgf´cm, 15 ft´lbf)
(n) Connect the camshaft position sensor connector.
(o) Connect the throttle position sensor connector.
(p) Connect the VSV connector for EVAP.
2. INSTALL FUEL PRESSURE PULSATION DAMPER
(See page SF±27)
3. INSTALL AIR INTAKE CHAMBER
(See page SF±49)
4. INSTALL ENGINE COVER
Install the engine cover with the 4 nuts.

SF0NL±05
B09506
B01608
B01982
LEXUS
Hand±Held
Tester SF±32
± SFI (2JZ±GE)THROTTLE BODY
1498 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
THROTTLE BODY
ON±VEHICLE INSPECTION
1. REMOVE ENGINE COVER
Remove the 4 nuts and engine cover.
2. INSPECT SYSTEM OPERATION
(a) Check that the throttle linkage moves smoothly.
(b) Inspect the throttle control motor for operating sound.
(1) Turn the ignition switch ON.
(2) When turning the accelerator pedal position sensor
lever, check the running sound of the motor. Also,
check that there is no friction sound.
If operation is not as specified, check the throttle control motor,
wiring and ECM.
(c) Inspect the throttle position sensor and accelerator pedal
position sensor function.
(1) Connect the LEXUS hand±held tester to the DLC3.
(2) When turning the accelerator pedal position sensor
lever to the full±open position, check that the
throttle valve opening percentage (THROTTLE
POS) of the CURRENT DATA showns the standard
value.
Throttle valve opening percentage: 60 % or more
If operation is not as specified, check that the throttle position
sensor, accelerator pedal position sensor, wiring and ECM.
(d) Start the engine, and check that the Malfunction Indicator
Lamp (MIL) does not light up.
(e) Inspect the air assist system.
(1) Allow the engine to warm up to normal operating
temperature.