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IF YOUR ENGINE STALLS WHILEDRIVING
If your engine stalls while driving . . .
1. Reduce your speed gradually, keeping a straight line. Move
cautiously off the road to a safe place.
2. Turn on your emergency flashers.
3. Turn the engine switch off, and try starting the engine again.
If the engine will not start, see ”If your vehicle will not start”\
.
CAUTION
If the engine is not running, the power assist for the
brakes and steering will not work, so steering and
braking will be much harder than usual.
IF YOUR VEHICLE WILL NOT START
(a) Simple checks
Before making these checks, make sure you have followed the
correct starting procedure instructions in ”Operating the
engine switch” on page 348 and that you have sufficient fuel.
Since your vehicle is equipped with the engine immobilizer,
also check whether the other keys will start the engine. If they
work, your electronic key may be broken. Have the key
checked at your Lexus dealer. If none of your keys work, there
may be a malfunction in the engine immobilizer. Call your
Lexus dealer. See ”Keys” on page 8.
If the engine is not turning over or is turning over too
slowly
1. Check that the battery terminals are tight and clean.
2. If the battery terminals are O.K., switch on the interior light.
3. If the light is out, dim or goes out when the starter is cranked,
the battery is discharged. You may try jump starting. See ”(c)
Jump starting” for further instruction.
4. If the engine does not start even after the battery has been
recharged or replaced, see “(d) Starting the engine after a
battery discharge” on page 472.
If the light is O.K., but the engine still will not start, it needs
adjustment or repair. Call a Lexus dealer, Roadside
Assistance or Customer Service Assistance. (See
”Foreword”.)
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471
G40027
GS300 5
Discharged battery 6Booster battery
GS300 only—Before carrying out the following procedure,
remove the engine compartment cover. (See page 512.)
JUMP STARTING PROCEDURE
1. If the booster battery is installed in another vehicle, make
sure the vehicles are not touching. Turn off all unnecessary
lights and accessories. When boosting, use the battery of matching or higher quality.
Any other battery may be difficult to jump start with.
If jump starting is difficult, charge the battery for several
minutes.
2. If required, remove all the vent plugs from the booster
battery. Lay a cloth over
the open vents on the booster battery.
(This helps reduce the explosion hazard, personal injuries and
burns.)
If the booster battery is an extended maintenance interval
battery, it is not necessary to remove the vent plugs.
3. If the engine in the vehicle with the booster battery is not
running, start it and let it run for about 5 minutes. During jump
starting, run the engine at about 2000 rpm with the accelerator
pedal lightly depressed.
4. Locate positive (+) and negative ( −) terminals of each
battery. Connect the jumper cables in the exact order (
1 2
3 4) shown in the illustration.
1 Connect a positive (red) jumper cable clamp to the
positive (+) terminal of the discharged battery.
2Connect the clamp at the other end of the positive (red)
cable to the positive (+) terminal of the booster battery.
3Connect a negative (black) cable clamp to the negative
(−) terminal of the booster battery.
4Connect the clamp at the other end of the negative (black)
cable to a solid, stationary, unpainted metallic point (such
as shown in the illustration) away from the battery. Do not
connect it to or near any part that moves when the engine
is cranked.
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CAUTION
When making the connections, to avoid serious injury,
do not lean over the battery or accidentally let the
jumper cables or clamps touch anything except the
correct battery terminals or the ground.
5. Charge the discharged battery with the jumper cables
connected for approximately 5 minutes. At this time, run the
engine in the vehicle with the booster battery at about 2000
rpm with the accelerator pedal lightly depressed.
6. Start your engine in the normal way. After starting, run it at
about 2000 rpm for several minutes with the accelerator pedal
lightly depressed.
7. Carefully disconnect the cables in the exact reverse order:
the negative cable and then the positive cable.
8. Carefully dispose of the battery cover cloths which may now
contain sulfuric acid.
9. If removed, replace all the battery vent plugs.
The engine may not restart even after battery charging or
replacement. If this happens, see “(d) Starting the engine after
a battery discharge”.
If the cause of your battery discharging is not apparent (for
example, lights left on), you should have it checked at your
Lexus dealer. If the first start attempt is not successful...
Check
that the clamp on the jumper cables are tight. Recharge
the discharged battery with the jumper cables connected for
several minutes and restart your engine in the normal way.
If another attempt is not successful, the battery may be
depleted. Have it checked at your Lexus dealer.(d) Starting the engine after a battery discharge
In the event that the battery is discharged, the engine may
not restart even after the battery is recharged or replaced.
For safety reasons, the engine may be disabled when
battery voltage is extremely low. If the engine is disabled,
the start system must be normalized.
To normalized the start system:
1. Shift the transmission to the “P” position and set the engine
switch off.
2. Open and close any of the doors.
3. Start the engine.