2014 Lexus GS450h cooling

663
GS450h_OM_OM30D52U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Engine compartment
■12-volt battery
→ P. 6 7 3
Engine oil level dipstick
(→P. 665)
Engine coolant reservoir (→P. 668)
Engine oil filler cap ( →P. 666)
Power control unit coolant
reservoir ( →P. 668) Brake fluid reservoir
(→P. 671)
Fuse box ( →P. 6 9 6 )
Washer fluid tank ( →P. 6 7 2 )
Electric cooling fans
Condenser ( →P. 6 7 0 )
Radiator ( →P. 6 7 0 )1
2
3
4
5
6
7
8
9
10
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GS450h_OM_OM30D52U_(U)
6696-3. Do-it-yourself maintenance
6
Maintenance and care
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized
water. (Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized
water. (Minimum temperature: -44 °F [-42 °C])
For more details about coolant, contact your Lexus dealer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have your Lexus dealer test the cap and check for leaks in
the cooling system.
CAUTION
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the cool-
ant inlet cap. ( →P. 800)
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water
and antifreeze must be used to provide proper lubrication, corrosion protection
and cooling. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
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702
GS450h_OM_OM30D52U_(U)
6-3. Do-it-yourself maintenance
34DOME7. 5
Personal lights, ornament lights, trunk light,
footwell lights, door courtesy lights, vanity
lights, rear door inside handle illuminations,
power trunk opener and closer
35MPX-B10
Body ECU, smart access system with push-
button start, electric tilt and telescopic steer-
ing column, power seats, head-up display,
front door ECU, gauges and meters, steer-
ing sensor, yaw rate and G sensor, overhead
module, RR CTRL SW, power trunk opener
and closer, clock, CAN gateway ECU
36IGCT NO.410Power control unit
37IGCT NO.37. 5Hybrid battery (traction battery), DC/DC
converter
38IGCT NO.25Hybrid system
39IG2 NO.15DCM, CAN gateway ECU
40GAUGE5Gauges and meters
41DC/DC150RH-J/B DC/DC, P/I DC/DC,
LH-J/B DC/DC, LUG-J/B DC/DC
42P/ I D C / D C100RR S/SHADE, DEFOG, FOG, TAIL,
PA N E L
43RH J/B DC/DC80Right-hand junction block
44LH J/B DC/DC50Left-hand junction block
45H-LP CLN30Headlight cleaner
46FA N N O. 240Electric cooling fans
47LUG J/B DC/DC80Luggage compartment junction block
48FA N N O.180Electric cooling fans
49PTC NO.150PTC heater
50PTC NO.250PTC heater
51HTR50Air conditioning system
FuseAmpereCircuit
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704
GS450h_OM_OM30D52U_(U)
6-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1STOP7. 5Stop lights, high mounted stoplight
2P/ W- B5Power window master switch
3P/ S E AT 1 F/ L30Po w e r s e a t s
4D/L NO.125Po w e r d o o r l o c k s y s t e m
5NV-IR10Lexus night view
6FL S/HTR10Seat heaters/ventilators
7WIPER30Windshield wipers
8WIPER-IG5Windshield wipers
9LH-IG10
Seat belts, body ECU, AFS, overhead mod-
ule, raindrop sensor, inside rear view mirror,
lane camera sensor (LKA), head-up display,
shift lock system, intuitive parking assist, front
left-hand door ECU, driver monitor system,
Remote Touch screen, electric tilt and tele-
scopic steering column, power seats, moon
roof, windshield wiper de-icer, intuitive park-
ing assist switch, PTC heater, headlight
cleaner
10LH ECU-IG10
VDIM, brake system, D-SW MODULE
(Blind Spot Monitor, heated steering wheel),
driver support system, AFS, electric cooling
fans, EPB, air conditioning system, steering
sensor
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708
GS450h_OM_OM30D52U_(U)
6-3. Do-it-yourself maintenance
■Tr u n k
FuseAmpereCircuit
1PSB30Pre-collision seat belts
2PTL25Power trunk opener and closer
3RR J/B-B10Smart access system with push-button start
4RR S/HTR20Seat heaters (rear)
5FR S/HTR10Seat heaters/ventilators (front)
6RR FOG10No circuit
7DC/DC-S (HV)7. 5DC/DC converter
8BATT FAN (HV)20Hybrid battery (traction battery) cooling fan
system
9SECURITY7. 5SECURITY
10ECU-B NO.37. 5Pa r k i n g b r a ke
11TRK OPN7. 5Power trunk opener and closer, trunk open
motor
12DCM (HV)7. 5DCM
13AC INV (HV)20Po w e r o u t l e t ( 1 2 0 V AC )
14RR-IG15Radar sensor, Blind Spot Monitor
15RR ECU-IG10
Power trunk opener and closer, parking
brake, tension reducer (rear left-hand), RR
CTRL SW, tire pressure warning system
16EPS-IG5Electric power steering system
17BACK UP7. 5Back-up lights
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7537-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
Indicates a malfunction in the Blind Spot Monitor
Indicates a malfunction in the smart access system
with push-button start
Indicates that the cooling performance of the hybrid
battery (traction battery) has dropped
Warning messageDetails
(If equipped)
(Flashes)
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800
GS450h_OM_OM30D52U_(U)
7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
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 following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( →P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( →P. 762) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
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8017-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary.
(→ P. 803)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
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 immediately
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 sys-
tem on and off repeatedly. (The fans may not operate in freezing tempera-
tures.)
If the fans are not operating:
Stop the hybrid system immediatel y and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
4
1
2
3
4
5
6
7
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