steering Lexus IS250 2008 Workshop Manual

331
4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
Fuse layout and amperage ratings■ Engine compartment (type A)
FuseAmpereCircuit
1ABS NO.325 AVDIM
2PWR HTR25 A
3TURN-HAZ15 AEmergency flashers, turn signals
4IG2 MAIN20 AIG2, IGN, GAUGE
5RAD NO.230 AAudio
6D/C CUT20 ADOME, MPX-B
7RAD NO.130 AAudio
8MPX-B10 A
Headlights, front fog lights, parking
lights, license plate lights, windshield
washer, horn, power door lock system,
power windows, power seats, electric
tilt and telescopic steering column,
meter, smart access system with push-
button start, outside rear view mirrors,
air conditioning system, security sys-
tem
9DOME10 AInterior lights, meter

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4-3. Do-it-yourself maintenance
08_IS350/250_U_(L/O_0708)
FuseAmpereCircuit
10E/G-B60 AFR CTRL-B, ETCS, ALT-S, steering
lock system, exhaust system
11DIESEL GLW80 A
12ABS150 AVSC, VDIM
13RH J/B-B30 APower door lock system, smart access
system with push-button start
14MAIN30 AHeadlight low beams
15STARTER30 ASmart access system with push-button
start
16LH J/B-B30 APower door lock system, SECURITY
17P/ I - B60 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
18EPS80 APo w e r s t e e r i n g
19ALT150 A
LH J/B-AM, E/G-AM, GLW PLG2,
HEATER, FAN1, FAN2, DEFOG,
ABS2, RH J/B-AM, GLW PLG1,
LH J/B-B, RH J/B-B
20GLW PLG150 APTC heater
21RH J/B-AM80 A
OBD, STOP SW, TI&TE, FR P/SEAT
RH, RAD NO.3, ECU-IG RH,
RH-IG, FR S/HTR RH, ACC, CIG,
PWR OUTLET
22ABS230 AVSC
23DEFOG50 ARear window defogger
24FA N 240 AElectric cooling fans
25FA N 140 AElectric cooling fans
26HEATER50 AAir conditioning system

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4-3. Do-it-yourself maintenance
08_IS350/250_U_(L/O_0708)■
Engine compartment (type B)
FuseAmpereCircuit
1FR CTRL-B25 AHeadlight high beam, horn
2A/F15 AExhaust system
3ETCS10 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
4ALT-S7. 5 ACharging system
5STR LOCK25 ASteering lock
6H-LP CLN30 AHeadlight cleaner
7A/C COMP7. 5 AAir conditioning system
8DEICER25 A
9FR CTRL-AM30 AFront fog lights, parking lights, wind-
shield washer
10IG210 AIgnition system
11EFI NO.210 AFuel system, exhaust system
12H-LP R LWR15 AHeadlight low beam (right)
13H-LP L LWR15 AHeadlight low beam (left)

336
4-3. Do-it-yourself maintenance
08_IS350/250_U_(L/O_0708)■
Driver’s side instrument panel
FuseAmpereCircuit
1FR P/SEAT LH30 APo w e r s e a t
2A/C7. 5 AAir conditioning system
3MIR HTR15 AOutside rear view mirror defoggers
4TV NO.110 ADisplay
5FUEL OPEN10 AFuel filler door opener
6TV NO.27. 5 A
7PSB30 APre-collision seat belt
8S/ROOF25 AElectric moon roof
9TA I L10 ATail lights, license plate lights, parking
lights
10PA N E L7. 5 ASwitch illumination, air conditioning
system, display
11RR FOG7. 5 A
12ECU-IG LH10 A
Cruise control, air conditioning sys-
tem, power steering, rain sensor, anti-
glare inside rear view mirror, shift lock
system, moon roof, tire inflation pres-
sure warning system
13FR S/HTR LH15 ASeat heaters and ventilators

338
4-3. Do-it-yourself maintenance
08_IS350/250_U_(L/O_0708)■
Passenger’s side instrument panel
FuseAmpereCircuit
1FR P/SEAT RH30 APo w e r s e a t
2DOOR DL15 A
3OBD7. 5 AOn-board diagnosis system
4STOP SW7. 5 AStop lights
5TI & TE20 AElectric tilt and telescopic steering
column
6RAD NO.310 AAudio
7GAUGE7. 5 AMeter
8IGN10 ASRS airbag system, cruise control,
steering lock system, fuel system
9ACC7. 5 A
Lexus link system, clock, air condition-
ing system, audio, display, outside rear
view mirrors, smart access system
with push-button start
10CIG15 ACigarette lighter
11PWR OUTLET15 APo w e r o u t l e t
12RR DOOR RH20 APo w e r w i n d o w s

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4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
FuseAmpereCircuit
13FR DOOR RH20 APo w e r w i n d o w s , o u t s i d e r e a r v i e w
mirrors
14AM215 ASmart access system with push-button
start
15RH-IG7. 5 A
Seat belts, intuitive parking assist,
automatic transmission, seat heater
and ventilator
16FR S/HTR RH15 ASeat heaters and ventilators
17ECU-IG RH10 A
Power seats, smart access system with
push-button start, AWD system, out-
side rear view mirrors, VDIM, VSC,
air conditioning system, pre-collision
seat belt, electric tilt and telescopic
steering, power windows, navigation
system
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. (
→P. 3 4 2 )
●If the replaced fuse blows again, have the vehicle inspected by your Lexus
dealer.
■If there is an overload in the circuits
The fuses are designed to blow before the entire wiring harness is damaged.

5
When trouble arises
351
5-1. Essential information
08_IS350/250_U_(L/O_0708)
■Emergency towing procedureRelease the parking brake.
Shift the shift lever to N.
Put the “ENGINE START STOP” switch in ACCESSORY mode (engine
off) or IGNITION ON mode (engine running).
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelets and the cables or chains.
●If the engine is not running, the power assist for the brakes and steering will not
function, making steering and braking more difficult.
NOTICE
■To prevent causing serious damage to the transmission
(vehicles with an automatic transmission)
Never tow this vehicle from the front with the rear wheels on the ground.
This may cause serious damage to the transmission.
■When towing a vehicle without using a towing dolly
(vehicles with a manual transmission)
The “ENGINE START STOP” switch must not be OFF.
STEP1
STEP2
STEP3

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5-1. Essential information
08_IS350/250_U_(L/O_0708)
Towing with a wheel lift-type truckFrom the front Vehicles with an automatic trans-
mission: Use a towing dolly under
the rear wheels.
Vehicles with a manual transmis-
sions: We recommend to use a
towing dolly under the rear wheels.
When not using a towing dolly,
release the parking brake and shift
the shift lever to N.
From the rear (2WD models)Switch to ACCESSORY mode so
that the steering wheel is
unlocked.
From the rear (AWD models) Use a towing dolly under the front
wheel.

5
When trouble arises
355
5-1. Essential information
08_IS350/250_U_(L/O_0708)
Using a flat bed truckIf your Lexus is transported by a
flat bed truck, it should be tied
down at the locations shown in the
illustration.
If you use chains or cables to tie
down your vehicle, the angles
shaded in black must be 45°.
Do not overly tighten the tie downs
or the vehicle may be damaged.
NOTICE
■To prevent causing serious damage to the transmission
(vehicles with an automatic transmission)
Never tow this vehicle from the front with the rear wheels on the ground.
■To prevent damaging the vehicle
●Do not tow the vehicle from the rear with the “ENGINE START STOP” switch
OFF.
The steering lock mechanism is not strong enough to hold the front wheel
straight.
●When raising the vehicle from the rear, ensure adequate ground clearance for
towing at the opposite end of the raised vehicle. Without adequate clearance, the
vehicle could be damaged while being towed from the rear.

358
5-1. Essential information
08_IS350/250_U_(L/O_0708)
Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a near
car crash event, this device may record some or all of the following infor-
mation:
● Engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver's seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
If your vehicles is equipped with a vehicle stability control (VSC) system
The VSC Electronic Control Unit (ECU) may contain another EDR. In
case the VSC or Brake Assist system is activated, or the lateral accelera-
tion is beyond a certain valve, this device may record some or all of the
following information:
●Behavior of the vehicle
● Steering wheel angle
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troubleshooting, there is an event data
recorder (EDR) that records data in a crash or a near car crash event.