cooling Lexus GS300h 2013 User Guide

7886-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
8F/PMP25Multiport fuel injection system/sequen-
tial multiport fuel injection system
9H-LP RH-LO20Right-hand headlight (low beam)*1
10H-LP LH-LO20Left-hand headlight (low beam)*1
11BATT FAN
(HV)*210Hybrid battery (traction battery) cooling
fan system
12ABS MAIN 210Brake system
13ABS MAIN 110Brake system
14IGCT NO.130IGCT NO.2, IGCT NO.3, IGCT NO.4,
IGCT NO.5
15ECU-B7.5VGRS, smart entry & start system
16INV W/P10Hybrid system
17ETCS10Multiport fuel injection system/sequen-
tial multiport fuel injection system
18EPS-B10Electric power steering system
19D/C CUT30DOME, MPX-B
20HORN10Horn
21ODS5No circuit
22TV7.5Remote Touch screen
23P/I-B NO.280IG2 MAIN, EFI MAIN, EDU, F/PMP,
A/F
24ABS NO.230Motor relay
25P/I-B NO.150H-LP HI RH, H-LP HI LH, DRL, emer-
gency brake signal
26H-LP LO30H-LP LO RH, H-LP LO LH
27LH J/B-B40Left-hand junction block
28RH J/B-B40Right-hand junction block
29VGRS40VGRS
30OIL PMP60Oil pump
FuseAmpereCircuit

7906-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
46LH J/B DC/DC50Left-hand junction block
47H-LP CLN30Headlight cleaner
48FAN NO.240Electric cooling fans
FuseAmpereCircuit

791 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)*
1: Low beam and high beam are the same bulb. (vehicles with discharge
headlights)
*
2: GS300h only.
49LUG J/B DC/DC80Luggage compartment junction block
50FAN NO.180Electric cooling fans
51PTC NO.150PTC heater
52PTC NO.250PTC heater
53HTR50Air conditioning system
54ABS NO.130Motor relay
55ECU-B NO.27.5Grill shutter
56DEICER25Windshield wiper de-icer
57ABS MAIN 310Brake system
58FILTER10Condenser
59A/C W/P7.5Air conditioning system
60SPARE10Spare fuse
61SPARE30Spare fuse
62SPARE20Spare fuse
FuseAmpereCircuit

793 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
10LH ECU-IG10
VDIM, brake system, D-SW MODULE
(Blind Spot Monitor, heated steering
wheel), driver support system, AFS,
electric cooling fans, EPB, air condition-
ing system, steering sensor
11DOOR FL30Outside rear view mirror defoggers,
power window (front left-hand)
12CAPACITOR
(HV)10Capacitor
13STRG LOCK15Steering lock system
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, brake system, power
management 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

8006-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Trunk
FuseAmpereCircuit
1PSB30Pre-crash seat belts
2PTL25Power trunk lid
3RR J/B-B10Smart entry & start system
4RR S/HTR20Seat heaters (rear)
5FR S/HTR10Seat heaters/ventilators (front)
6RR FOG10Rear fog light
7DC/DC-S (HV)7.5DC/DC converter
8BATT FAN (HV)20Hybrid battery (traction battery) cooling
fan system
9SECURITY7.5SECURITY
10ECU-B NO.37.5Parking brake
11TRK OPN7.5Power trunk lid, trunk open motor
12DCM (HV)7.5No circuit
13AC INV (HV)20No circuit
14RR-IG15Radar sensor, Blind Spot Monitor
15RR ECU-IG10
Power trunk lid, parking brake, tension
reducer (rear left-hand), RR CTRL SW,
tire pressure warning system
16EPS-IG5Electric power steering system
17BACK UP7.5Back-up light

8477-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Indicates that the cooling performance of the
hybrid battery (traction battery) has dropped
Indicates that the grille shutter system cannot
operate or the grille shutter is dirty or covered
with ice
Wa r n i n g m e s s a g eDetails

9187-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
After the hybrid system has cooled down sufficiently, inspect
the hoses and cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact your Lexus
dealer.
The coolant level is satisfactory if it is between the “FULL”
and “LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
3
1
2
GS300hGS450h
4
1
2
3
4
GS300hGS450h

9197-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Add coolant if necessary. (P. 923)
Water can be used in an emergency if engine coolant is unavailable.
Start the hybrid system and turn the air conditioning system on
to check that the radiator cooling fans operate and to check for
coolant leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is difficult to check these, turn the air
conditioning system on and off repeatedly. (The fans may not operate in
freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
5
GS300hGS450h
6
7

9207-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
If “Hybrid System Overheat” is shown on the multi-information
display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses
and radiator core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact your Lexus
dealer.
The coolant level is satisfactory if it is between the “F”/
“FULL” and “L”/“LOW” lines on the reservoir.
Reservoir
“F”/“FULL”
“L”/“LOW”
1
2
3
1
2
GS300hGS450h
4
1
2
3
GS300hGS450h

9247-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
If steam is seen coming from under the hood, do not open the hood until
the steam has subsided. The engine compartment may be very hot.
After the hybrid system has been turned off, check that the indicator on
the power switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automati-
cally start, or the cooling fan may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fan,
which may lead to fingers or clothing (especially a tie, a scarf or a muf-
fler) getting caught, resulting in serious injury.
Do not loosen the coolant inlet cap or
the coolant reservoir caps while the
hybrid system and radiator are hot.
High temperature steam or coolant
could spray out.