Page 726 of 914
7086-3. Do-it-yourself maintenance
GS350/250_EE (OM30C36E)
Right-hand drive vehicles
FuseAmpereCircuit
1RH J/B ALT80Right-hand junction block
2P/I ALT100RR DEF, TAIL, FR FOG, DEICER,
PANEL, RR S/SHADE
3ALT150
RH J/B ALT, P/I ALT, alternator, LH J/B
ALT, luggage compartment junction
block
4P/I-B NO.280F/PMP, EFI MAIN, A/F HTR, EDU, IG2
MAIN
5RH J/B-B40Right-hand junction block
6VGRS40No circuit
7LH J/B-B40Left-hand junction block
8PTC NO.250PTC heater
9PTC NO.150PTC heater
10LUG J/B ALT50Luggage compartment junction block
11ABS NO.140VDIM
12HTR50Air conditioning system
13ARS80No circuit
14EPS80EPS
15DOME7.5
Personal lights, ornament lights, trunk
light, footwell lights, door courtesy
lights, vanity lights, rear door inside han-
dle illuminations, power trunk lid
Page 727 of 914

709 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS350/250_EE (OM30C36E)
16MPX-B10
Smart entry & start system, electric tilt
and telescopic steering column, power
seats, head-up display, front right-hand
door ECU, gauges and meters, steering
sensor, yaw rate and G sensor, overhead
module, front left-hand door ECU,
power trunk lid, clock, body ECU, RR
CTRL SW, CAN gateway ECU
17FILTER10Condenser
18A/C COMP7.5Air conditioning system
19H-LP CLN30Headlight cleaner
20FAN NO.240Electric cooling fans
21LH J/B ALT60Left-hand junction block
22FAN NO.180Electric cooling fans
23P/I-B NO.150H-LP HI RH, H-LP HI LH, DRL, emer-
gency brake signal
24EPB30Parking brake
25LUG J/B-B40Luggage compartment junction block
26R/B-B20EPS-B, TV
27HORN10Horn
28ETCS10Multiport fuel injection system/sequen-
tial multiport fuel injection system
29ALT-S7.5Charging system
30ECU-B7.5Smart entry & start system
31DCM7.5DCM
32D/C CUT30DOME, MPX-B
33ABS NO.250VDIM
34ST30Starting system
35H-LP LO30Headlights, H-LP RLY
FuseAmpereCircuit
Page 731 of 914
713 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS350/250_EE (OM30C36E)
10LH ECU-IG10
VDIM, D-SW MODULE (Blind Spot
Monitor, heated steering wheel), driver
support system, AFS, EPB
11DOOR FL30Outside rear view mirror defoggers,
power window (front left-hand)
12CAPACITOR
(HV)10No circuit
13STRG LOCK15Steering lock
14D/L NO.225Power door lock system
15DOOR RL30Power window (rear left-hand)
16HAZ15Turn signal lights, emergency flashers
17LH-IG210
Multiport fuel injection system/sequen-
tial multiport fuel injection system, stop
lights, smart entry & start system, steer-
ing lock system
18LH J/B-B7.5Body ECU
19S/ROOF20Moon roof
20P/SEAT2 F/L25Power seats
21TI & TE20Electric tilt and telescopic steering col-
umn
22A/C7.5Air conditioning system
FuseAmpereCircuit
Page 732 of 914
7146-3. Do-it-yourself maintenance
GS350/250_EE (OM30C36E)
Right-hand drive vehicles
FuseAmpereCircuit
1P/SEAT1 F/L30Power seats
2D/L NO.125Power door lock system
3NV-IR10No circuit
4FL S/HTR10Seat heaters/ventilators
5STRG HTR15Heated steering wheel
6WIPER-IG5Windshield wipers
7LH-IG10
Seat belts, body ECU, AFS, Remote
Touch screen, overhead module, rain-
drop sensor, moon roof, inside rear view
mirror, LKA, front left-hand door ECU,
Lexus parking assist-sensor, power seats,
CAN gateway ECU
8LH ECU-IG10Yaw rate and G sensor, air conditioning
system, AFS, driver support system
9DOOR FL30Outside rear view mirror defoggers,
power window (front left-hand)
10CAPACITOR
(HV)10No circuit
11AM27.5Power management system, smart entry
& start system
12D/L NO.225Power door lock system
13DOOR RL30Power window (rear left-hand)
14HAZ15Turn signal lights, emergency flashers
Page 733 of 914
715 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS350/250_EE (OM30C36E)
15LH-IG210
Multiport fuel injection system/sequen-
tial multiport fuel injection system, stop
lights, smart entry & start system, steer-
ing lock system
16LH J/B-B7.5Body ECU
17S/ROOF20Moon roof
18P/SEAT2 F/L25Power seats
19A/C7.5Air conditioning system
FuseAmpereCircuit
Page 734 of 914
7166-3. Do-it-yourself maintenance
GS350/250_EE (OM30C36E)
Right side instrument panel
Left-hand drive vehicles
FuseAmpereCircuit
1P/SEAT1 F/R30Power seats
2FR P/OUTLET15Power outlet (front)
3RR P/OUTLET15Power outlet (rear)
4P/SEAT2 F/R25Power seats
5AV S20AV S
6STRG HTR15Heated steering wheel
7WA S H20Windshield washer
8RH ECU-IG10Navigation system, pre-crash seat belts,
air conditioning system
9RH-IG10
Tension reducer, seat heater/ventilator
switches, AWD system, front right-hand
door ECU, nanoe, CAN gateway ECU,
tire pressure warning system, power
seats, driver monitor system
10DOOR FR30
Front right-hand door control system
(outside rear view mirror defoggers,
power window)
Page 768 of 914

747
7 7-2. Steps to take in an emergency
When trouble arises
GS350/250_EE (OM30C36E)
If you think something is wrong
Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
Flat-looking tires or uneven tire wear
Engine coolant temperature gauge needle continually points
higher than normal.
Changes in exhaust sound
Excessive tire squeal when cornering
Strange noises related to the suspension system
Pinging or other noises related to the engine
Engine missing, stumbling or running roughly
Appreciable loss of power
Vehicle pulls heavily to one side when braking
Vehicle pulls heavily to one side when driving on a level road
Loss of brake effectiveness, spongy feeling, pedal almost
touches the floor
If you notice any of the following symptoms, your vehicle proba-
bly needs adjustment or repair. Contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped profes-
sional as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
Page 851 of 914
8307-2. Steps to take in an emergency
GS350/250_EE (OM30C36E)
If your vehicle overheats
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from under the hood.
If you see steam:
Stop the engine. Carefully lift the hood after the steam subsides
and then restart the engine.
If you do not see steam:
Leave the engine running and carefully lift the hood.
Check to see if the cooling fan is operating.
If the fan is operating:
Wait until the temperature of the engine (shown on the instru-
ment panel) begins to fall and then stop the engine.
If the fan is not operating:
Stop the engine immediately and call any authorized Lexus
dealer or repairer, or another duly qualified and equipped profes-
sional.
After the engine has cooled
down sufficiently, check the
engine coolant level and
inspect the radiator core (radi-
ator) for any leaks.
If the engine compartment cover
needs to be removed: P. 6 6 1
1
2
3
4