Page 545 of 784
545
ES350_300h_OM_OM33B99U_(U)
7-3. Do-it-yourself maintenance
7
Maintenance and care
Engine compartment
Gasoline vehicles (2GR-FE engine)
Washer fluid tank (P. 561)
Engine oil filler cap (P. 550)
Engine oil level dipstick (P. 548)
Engine coolant reservoir (P. 553) Brake fluid reservoir
(P. 5 5 6 )
Fuse box ( P. 586)
12-volt battery ( P. 5 5 7 )
Electric cooling fans
Condenser ( P. 555)
Radiator ( P. 555)1
2
3
4
5
6
7
8
9
10
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546
ES350_300h_OM_OM33B99U_(U)
7-3. Do-it-yourself maintenance
Hybrid vehicles (2AR-FXE engine)
■12-volt battery (hybrid vehicles)
P. 5 6 2
Washer fluid tank ( P. 561)
Fuse boxes ( P. 586)
Power control unit coolant
reservoir ( P. 553)
Engine oil level dipstick (P. 548)
Engine oil filler cap (P. 550) Engine coolant reservoir
(P. 553)
Brake fluid reservoir (P. 5 5 6 )
Power control unit coolant
radiator ( P. 555)
Electric cooling fans
Condenser ( P. 555)
Engine coolant radiator (P. 555)1
2
3
4
5
6
7
8
9
10
11
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554
ES350_300h_OM_OM33B99U_(U)
7-3. Do-it-yourself maintenance
■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 [-35C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized
water. (Minimum temperature: -44 F [-42C])
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 engine is hot
Do not remove the engine/power control un it coolant reservoir cap or the radiator
cap.
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.
Page 590 of 784
590
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7-3. Do-it-yourself maintenance
FuseAmpereCircuit
1WIP-S5Driver support system, windshield wipers
2FA N50Electric cooling fan
3H-LP CLN30No circuit
4ENG W/PMP*130Cooling system
5PTC HTR NO.250PTC heater
6PTC HTR NO.150PTC heater
7HTR50Air conditioning system
8ALT*2140Charging system
DC/DC*1120Hybrid system
9ABS NO.2*230VSC, ABS
10ST/AM2*230Starting system
ABS NO.1*130VSC, ABS
11H-LP-MAIN30H-LP RH-LO, H-LP LH-LO
12ABS MTR NO.2*150VSC, ABS
13ABS NO.1*250VSC, ABS
ABS MTR NO.1*150VSC, ABS
14R/B NO.2*150IGCT MAIN, INV W/PMP
15EPS80Electric power steering
16S-HORN7. 5S-HORN
17DEICER15Windshield wiper de-icer
18HORN10Horn
19TV15
Multi-information display, audio display,
Remote Touch, audio system, gauges and
meters
20AMP NO.230Audio system
21EFI NO.215
Multiport fuel injection system, sequential
multiport fuel system, electronic controlled
transmission
Page 593 of 784
ES350_300h_OM_OM33B99U_(U)
5937-3. Do-it-yourself maintenance
7
Maintenance and care
■Engine compartment (type B fuse box) (hybrid vehicles only)
FuseAmpereCircuit
1BATT FAN7. 5Battery cooling fan
2INV W/PMP RLY7. 5INV W/PMP RLY
3DC/DC IGCT10Hybrid system
4INV7. 5Hybrid system
5BATT VL SSR10Hybrid system
6PM IGCT7. 5Power management system, hybrid system
7IGCT-MAIN25INV W/PMP RLY, INV, DC/DC IGCT,
BATT VL SSR, PM IGCT, BATT FAN
8INV W/PMP15Hybrid system
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594
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7-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1ECU-IG1 NO.210
Main body ECU, audio system, shift lock sys-
tem, outside mirror control ECU, tension
reducer, windshield wipers, heated steering
wheel, multi-information display, audio dis-
play, intuitive parking assist, tire pressure
warning system, moon roof, auto anti-glare
inside rear view mirror, raindrop sensor, rear
sunshade, wireless door lock system, power
trunk opener and closer ECU
2ECU-IG1 NO.110
Electric cooling fan, windshield wiper de-
icer, VSC, ABS, charging system, steering
sensor, electronic controlled transmission,
electric power steering, gateway ECU, elec-
tric tilt and telescopic steering column
3PA N E L N O. 25Clock
4TA I L15Parking lights, side marker lights, license
plate lights
5DOOR F/R20Power window, outside mirror control ECU
6DOOR R/R20Po w e r w i n d o w
7DOOR F/L20Power window, outside mirror control ECU
8DOOR R/L20Po w e r w i n d o w
9H-LP LVL7. 5Automatic headlight leveling system
10WA S H E R10Windshield washer
11A/C-IG17. 5Air conditioning system, PTC heater, gauges
and meters, seat heaters and ventilators
Page 648 of 784

6488-2. Steps to take in an emergency
ES350_300h_OM_OM33B99U_(U)
■Warning message in radar cruise mode (if equipped)
In the following cases, the warning message may not be displayed even if vehicle-to-
vehicle distance decreases:
●When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
■The LDA (Lane Departure Alert) system (if equipped)
In the following cases, the warning message will not be displayed even if the vehicle
deviates from the lane markers.
●When the vehicle speed deviates from the operating range of the LDA system
functions
●When the lane markers cannot be recognized
Carrying out the corresponding action turns the messages off.
Other displayed messages
Displayed messageDetailsCorrection procedure
Maintenance of the
hybrid system (traction
battery) cooling compo-
nent is required The filter may be
clogged, the air vent
may be blocked or
there may be a gap in
the duct.
Have maintenance per-
formed on the hybrid sys-
tem (traction battery)
cooling component at
your Lexus dealer.
Page 683 of 784

6838-2. Steps to take in an emergency
ES350_300h_OM_OM33B99U_(U)
8
When trouble arises
CAUTION
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte, while
related parts contain lead and lead compounds. Observe the following precau-
tions when handling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and take care
not to allow any battery fluids (acid) to co me into contact with skin, clothing or the
vehicle body.
●Do not lean over the 12-volt battery.
●In the event that battery fluid comes into contact with the skin or eyes, immedi-
ately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received.
●Always wash your hands after handling th e battery support, terminals, and other
battery-related parts.
●Do not allow children near the 12-volt battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in
the cooling fans or engine drive belt.