brakes lexus LS400 1999 Electrical Components / LEXUS 1999 LS400 OWNER'S MANUAL (OM50514U)

GAUGES, METERS AND SERVICE REMINDER INDICATORS
64
(a) Brake System Warning Light
This light has the following two functions:
Parking brake reminder
If this light is on, make sure the parking brake is fully
released. The light should go off.
Low brake fluid level warning
If this light comes on and stays on while you are driving,
slow down and pull off the road. Then stop the vehicle
carefully. Remember that stopping distance and pedal
effort may be increased. There may be a problem
somewhere in the brake system. Check the fluid level
of the see±through reservoir.
To make sure the parking brake has not caused the
warning light to come on, check to see that the parking
brake is fully released.
If the brake fluid level is low ...
At a safe place, test your brakes by starting and
stopping.
If you judge that the brakes still work adequately, drive
cautiously to your nearest dealer or shop for repairs.
 If the brakes are not working, have the vehicle towed
in for repairs. (For towing information, see page 366.)

STARTING AND DRIVING
305
31L052±1
When you turn the ignition switch on, this system
always turns on. Leave the system on during
ordinary driving so that it can operate when needed.
When traction control is applied, the slip indicator
light blinks.
You may hear a sound in the engine compartment for a
few seconds when the engine is started or just after the
vehicle is started. This means that the traction control
system is in the self ±check mode, and does not indicate
malfunction.
When the traction control system is operating, you may
feel vi bration of your vehicle, caused by operation of the
brakes. This indicates the system is functioning
properly. When getting the vehicle out of mud or new snow, etc.
the traction control system will help operate to prevent
the wheels from spinning.
To turn off the traction control system, see page 309.

STARTING AND DRIVING
307
VEHICLE SKID CONTROLSYSTEM
The vehicle skid control system helps to provide
comprehensive control of the systems such as an
anti±lock brake system, traction control, engine
control, electronically modulated air suspension,
etc. This system automatically controls the output
of the brakes or engine to help prevent the vehicle
from skidding when cornering on a slippery road
surface or abrupt steering wheel operation occurs.
31L052±1

STARTING AND DRIVING
313
BRAKE SYSTEM
The tandem master cylinder brake system is a hydraulic
system with two separate sub±systems. If either
sub±system should fail, the other will still work.
However, the pedal will be harder to press, and your
stopping distance will be longer. Also, the brake system
warning light may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake booster
The brake booster uses engine vacuum to power±assist
the brakes. If the engine should quit while you are
driving, you can bring the vehicle to a stop with normal
pedal pressure. There is enough reserve vacuum for
one or two stops but no more!

STARTING AND DRIVING
314
CAUTION
Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your vacuum
reserve.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard ± much harder than normal. And your braking
distance will be longer.

DRIVING TIPS
323
BREAK±IN PERIOD
Drive gently and avoid high speeds.
You need not follow a break±in schedule with your new
Lexus. But following a few simple tips for the first 1600
km (1000 miles) can add to the future economy and long
life of your vehicle:
Do not drive over 88 km/h (55 mph).
 Avoid overrevving. Maintain engine speed between
2000 and 4000 rpm.
 Avoid full±throttle starts.
 Try to avoid hard stops during the first 300 km (200
miles).
 Do not drive for a long time at any single speed, either
fast or slow.
 Do not tow a trailer during the first 800 km (500 miles).
OPERATION IN FOREIGN
COUNTRIES
If you plan to drive your Lexus in another country ...
First, comply with the vehicle registration laws.
Second, confirm the availability of the correct fuel
(unleaded and minimum octane rating).
TIPS FOR DRIVING IN VARIOUS CONDITIONS
Always slow down in gusty crosswinds. This will
allow you much better control.
 Drive slowly onto curbs and, if possible, at a right
angle. Avoid driving onto high, sharp±edged objects
and other road hazards. Failure to do so can lead to
severe tire damage resulting in tire bursts.
 When parking on a hill, turn the front wheels until they
touch the curb so that the vehicle will not roll. Apply
the parking brake, and place the transmission in ºPº.
If necessary, block the wheels.
 Washing your vehicle or driving through deep water
may get the brakes wet. To see whether they are wet,
check that there is no traffic near you and then press
the pedal lightly. If you do not feel a normal braking
force, the brakes are probably wet. To dry them, drive
the vehicle cautiously while lightly pressing the brake
pedal with the parking brake applied. If they still do
not work safely, pull to the side of the road and call a
Lexus dealer for assistance.
CAUTION
 Before driving off, make sure the parking brake is
fully released and that the parking brake reminder
light is off.

DRIVING TIPS
324
Do not rest your foot on the brake pedal while
driving. It can cause dangerous overheating,
needless wear, and poor fuel economy.
 To drive down a long or steep hill, reduce your
speed and downshift. Remember, if you ride
the brakes excessively, they may overheat and
not work properly. See page 288.
 Be careful when accelerating, upshifting,
downshifting or braking on a slippery surface.
The abrupt change in engine speed, such as
sudden acceleration or engine braking, could
cause the vehicle to spin or skid.
 Do not drive in excess of the speed limit. Even
if the legal speed limit permits it, do not drive
over 140 km/h (85 mph) unless your vehicle has
high±speed capability tires. Driving over 140
km/h (85 mph) may result in tire failure, loss of
control and possible injury. Be sure to consult
a tire dealer to determine whether the tires on
your vehicle are high±speed capability tires or
not before driving at such speeds.
 Do not continue normal driving when the
brakes are w et. If they are wet, your vehicle will
require a longer stopping distance, and it may
pull to one side when the brakes are applied.
Also, the parking brake will not hold the vehicle
securely.WINTER DRIVING TIPS
Make sure you have a proper freeze protection of
engine coolant.
Your coolant must contain ethylene±glycol type coolant
for a proper corrosion protection of aluminum
components. Use ºToyota Long Life Coolantº or
equivalent. See ºChecking the engine coolant levelº on
page 409 for instructions.
NOTICE
Do not use alcohol type antifreeze or plain water
alone.
When it is extremely cold, we recommend to use 60%
solution for your Lexus, to provide protection down to
about ±50 C (±58 F). Do not use more than 70%
solution for better coolant performance.
Check the condition of the battery and cables.
Cold temperatures reduce the capacity of any battery, so
it must be in top shape to provide enough power for
winter starting. Page 443 tells you how to visually
inspect the battery. Your Lexus dealer and most service
stations will be pleased to check the battery charge
level.
Make sure the engine oil viscosity is suitable for the
cold weather.

DRIVING TIPS
331
Brakes and safety chains
Lexus recommends trailers with brakes that
conform to any applicable federal and
state/provincial regulations.
 A safety chain must always be used between the
towing vehicle and the trailer. Leave sufficient
slack in the chain for turns. The chain should
cross under the trailer tongue to prevent the
tongue from dropping to the ground in case it
becomes damaged or separated. For correct
safety chain procedures, follow the hitch or trailer
manufacturer's recommendations.
CAUTION
 If the total trailer weight exceeds 450 kg (1000 lb.),
trailer brakes are required.
 Never tap into your vehicle's hydraulic system as it
will lower its braking effectiveness.
 Never tow a trailer without using a safety chain
securely attached to both the trailer and the vehicle.
If damage occurs to the coupling unit or hitch ball,
there is possible danger of the trailer wandering over
into another lane.

DRIVING TIPS
334
Avoid jerky steering and sharp turns. The trailer could
hit your vehicle in a tight turn. Slow down before
making a turn to avoid the need of sudden braking.
 Remember that when making a turn, the trailer
wheels will be closer than the vehicle wheels to the
inside of the turn. Therefore, compensate for this by
making a larger than normal turning radius with your
vehicle.
 Crosswinds and rough roads will adversely affect
handling of your vehicle and trailer, causing sway.
Pay attention to the rear from time to time to prepare
yourself for being passed by large trucks or buses,
which may cause your vehicle and trailer to sway. If
swaying happens, firmly grip the steering wheel and
reduce speed immediately but gradually. Never
increase speed. If it is necessary to reduce speed,
brake slowly. Steer straight ahead. If you make no
extreme correction with the steering or brakes, your
vehicle and trailer will stabilize.
 Be careful when passing other vehicles. Passing
requires considerable distance. After passing a
vehicle, do not forget the l ength of your trailer and be
sure you have plenty of room before changing lanes.
 In order to maintain efficient engine braking and
electrical charging performance, do not use
overdrive. Transmission must be in the º4º position. 
Because of the added load of the trailer, your vehicle's
engine may overheat on hot days (at temperatures
over 30C [85F]) when going up a long or steep
grade with a trailer. If the engine coolant temperature
gauge indicates overheating, immediately turn off the
air conditioning (if in use), pull your vehicle off the
road and stop in a safe spot. See ºIf your vehicle
overheatsº on page 347 of this manual.
 Always place wheel blocks under both the vehicle
and trailer wheels when parking. Apply the parking
brake firmly. Put the transmission in ºPº. Avoid
parking on a slope with a trailer, but if it cannot be
avoided, do so only after performing the following:
1. Apply the brakes and keep them applied.
2. Have someone place wheel blocks under both the
vehicle and trailer wheels.
3. When the wheel blocks are in place, release your
brakes slowly until the blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into ºPº and turn off the engine.

DRIVING TIPS
335
When restarting out after parking on a slope:
1. With
the transmission in ºPº position, start the engine.
Be sure to keep the brake pedal depressed.
2. Shift into the º3º, º2º, ºLº or ºRº position.
3. Release the parking brake and brake pedal and
slowly pull or back away from the wheel blocks. Stop
and apply your brakes.
4. Have someone retrieve the blocks.
CAUTION
 Do not exceed 72 km/h (45 mph) or the posted towing
speed limit, whichever is lower. Because instability
(swaying) of a towing vehicle±trailer combination
usually increases as the speed increases, exceeding
72 km/h (45 mph) may cause loss of control.
 Slow down and downshift before descending steep
or long downhill grades. Do not make sudden
downshifts.
 Avoid holding the brake pedal down too long or too
frequently. This could cause the brakes to overheat
and result in reduced braking efficiency.