Page 470 of 622
469
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
GS350
FuseAmpereCircuit
1ECU-B10VGRS, EPS, driver’s seat switch
module, Lexus link system ECU
2ABS MAIN325Electronically controlled
brake system
3TURN-HAZ15Turn signal lights, emergency flashers
4IG2 MAIN20IG2, GAUGE and IGN
5RAD NO.230Audio system
6D/C CUT20DOME and MPX-B
7RAD NO.130Audio system
8MPX-B10
Multiplex communication system,
front controller, door control system
(power door lock system, door cour-
tesy lights, power windows, power
rear view mirror control system, out-
side rear view mirror heaters), power
seat system, steering sensors, elec-
tronically controlled brake system, tilt
and telescopic steering wheel,
gauges and meters, combination
switch
GS_U_G.book Page 469 Monday, April 27, 2009 10:50 AM
Page 471 of 622
470
4-3. Do-it-yourself maintenance
GS_G_U (OM30B43U)
May 14, 2009 1:16 pm
FuseAmpereCircuit
9DOME10
Foot lights, vanity lights, gauges and
meters, steering spot light, steering
switch illumination, rear personal
lights, automatic transmission selec-
tor lever spot light, front personal
lights
10CDS10Noise filter
11ABS MAIN210Electronically controlled
brake system
12ABS MOTOR30ABS
13ABS MAIN110Capacitor
14E/G-B60FR CTRL BATT, ETCS, ALT-S and
A/F HTR
15ABS150VDIM
16RH J/B-B30AM2, DOOR FR and DOOR RR
17VGRS40VGRS
18MAIN30H-LP R LWR and H-LP L LWR
19STARTER30Starting system
20LH J/B-B30FL DOOR, RL DOOR and RAD
NO.3
21P/ I - B60EFI NO.1, F/PMP and INJ
22EPS80EPS
23ALT150
RH J/B-AM, LH J/B-AM, E/G-AM,
RR JB, HEATER, DEFOG, FAN1,
FAN2, ABS2, ABS MOTOR,
ABS MAIN1, and ABS MAIN2
sec_04_03.fm Page 470 Thursday, May 14, 2009 1:16 PM
Page 478 of 622
477
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
FuseAmpereCircuit
8FUEL OPN10Fuel filler door opener, trunk lid
opener
9ECU-IG LH10
VDIM, electronically controlled
brake system, yaw rate and G sensor,
steering sensor, cruise control sys-
tem, dynamic radar cruise control
system, EPS, VGRS, rear view moni-
tor system, four-wheel drive system,
front controller, moon roof, rain sen-
sor
10FR S/HTR LH15Seat heaters and ventilators
11RR DOOR LH20
Rear left door control system (power
door lock system, door courtesy light,
power window)
12FR DOOR LH20
Front left door control system (power
door lock system, power rear view
mirror control system, door courtesy
light, outside rear view mirror heater,
power window)
13RAD NO.310Audio system
14H-LP LVL7. 5AFS, automatic headlight leveling
control system
GS_U_G.book Page 477 Monday, April 27, 2009 10:50 AM
Page 480 of 622
479
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
■Right side instrument panel
FuseAmpereCircuit
1FR P/SEAT RH30Power seat system
2OBD7. 5On-board diagnosis system
3STOP SW7. 5
Stop/tail lights, multi-port fuel injec-
tion system/sequential multiport fuel
injection system, starting system,
electronically controlled brake sys-
tem, Enhanced VSC system, shift
lock system, ECT ECU
4AM17. 5
5TI&TE20Tilt and telescopic steering wheel,
multiplex communication system
6SECURITY7. 5Smart access system with push-but-
ton start
7STR LOCK25Steering lock system
8GAUGE7. 5Gauges and meters
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480
4-3. Do-it-yourself maintenance
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
FuseAmpereCircuit
9IGN10
Multi-port fuel injection system/
sequential multiport fuel injection
system, SRS airbag system, stop/tail
lights, steering lock system, electroni-
cally controlled brake system, Lexus
link system ECU, occupant classifica-
tion system ECU
10ACC7. 5
Multiplex communication system,
smart access system with push-but-
ton start, rear view monitor system,
audio system, air conditioning system,
Lexus link system ECU
11CIG15Cigarette lighter
12PWR OUTLET15Po w e r o u t l e t
13AIR SUS20Adaptive variable suspension system
14RR DOOR RH20
Rear right door control system
(power door lock system, door cour-
tesy light, power window)
15FR DOOR RH20
Front right door control system
(power door lock system, power rear
view mirror control system, door
courtesy light, outside rear view mir-
ror heater, power window), multiplex
communication system
GS_U_G.book Page 480 Monday, April 27, 2009 10:50 AM
Page 508 of 622

5
When trouble arises
507
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continui ng to drive the vehicle may be
dangerous.
The following warning in dicates a possible problem in the brake system.
Immediately stop the vehi cle in a safe place and contact your Lexus
dealer.
*1: Parking brake engaged warning buzzer:
→ P. 5 2 2
Stop the vehicle immediately.
The following warning indicates the po ssibility of damage to the vehicle
that may lead to an ac cident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer) *1
•Low brake fluid
• Malfunction in the brake system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released, the system is operating normally.
Warning lightWarning light/Details
Charging system warning lightMalfunction in the vehicle’s charging system.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, bu t then turns off, this does not necessar-
ily indicate a malfunction in the system.
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508
5-2. Steps to take in an emergency
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
Have the vehicle inspected immediately.Failure to investigate th e cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lamp
Malfunction in:
• The emission control system;
• The electronic engine control system;
• The electronic throttle control system; or
• The automatic transmission control system.
SRS warning lightMalfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
ABS warning lightMalfunction in:
•The ABS; or
• The brake assist system.
(GS460)
ECB (Electronically controlled brake system) warning light Malfunction in the electronically controlled brake system.
Electric power steering system warning lightMalfunction in the EPS.
“PCS” warning light (if equipped)Malfunction in the pre-collision system.
Slip indicatorMalfunction in the Enhanced VSC.
The indicator will blink when Enhanced VSC, TRAC or hill-
start assist control is operational. ( →P. 2 0 1 )
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5
When trouble arises
513
5-2. Steps to take in an emergency
GS_G_U (OM30B43U)
April 27, 2009 10:48 am
CAUTION
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Vehicles with standard tires:
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflationpressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Check the tires. If the tire is
flat, change to the spare tire and have the flat tire repaired by the nearest
Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
●Vehicles with run-flat tires:
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 55 mph (90 km/h).
• Check and adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Have the tire replaced by
the nearest Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
GS_U_G.book Page 513 Monday, April 27, 2009 10:50 AM