Page 709 of 908
ES350 300h_OM_OM33A01U_(U)
7096-3. Do-it-yourself maintenance
6
Maintenance and care
Slide and pull out the filter.
Replace it with a new one.
The “UP” marks shown on the filter
should be pointing up.
■Checking interval
Inspect and replace the air conditioning f ilter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
required. (For scheduled maintenance information, please refer to the “Owner’s
Manual Supplement” or “S cheduled Maintenance”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
5
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the system.
Page 716 of 908
716
ES350 300h_OM_OM33A01U_(U)
6-3. 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 deicer
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 720 of 908

720
ES350 300h_OM_OM33A01U_(U)
6-3. 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
FAN, DEICER, VSC, ABS, charging system,
steering sensor, electronic controlled trans-
mission, electric power steering, gateway
ECU, electric tilt and telescopic steering col-
umn
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 721 of 908

ES350 300h_OM_OM33A01U_(U)
7216-3. Do-it-yourself maintenance
6
Maintenance and care
12WIPER25Windshield wipers
13BKUP LP7. 5
Multiport fuel injection system, sequential
multiport fuel system, electronic controlled
transmission, audio system, navigation sys-
tem, back-up lights
14FUEL OPN10Fuel filler door opener
15EPS-IG110Electric power steering
16P/O U T L E T R R15Po w e r o u t l e t
17RADIO-ACC5Audio system, Remote Touch, multi-informa-
tion display, audio display, navigation system
18S/HTR&FAN F/R10Seat heaters and ventilators
19S/HTR&FAN F/L10Seat heaters and ventilators
20OBD7. 5On-Board diagnosis system
21ECU-B NO.210
Power window master switch, air condition-
ing system, smart access system with push-
button start, tire pressure warning system,
rear sunshade
22STRG HTR10Heated steering wheel
23PTL25Power trunk opener and closer ECU
24STOP7. 5
Power management system, multiport fuel
injection system, sequential multiport fuel
system, VSC, ABS, electronic controlled
transmission, driver support system, engine
room junction block assy, tail lights, high
mounted stoplight, smart access system with
push-button start, shift lock system
25P/ S E AT F/ L30Po w e r s e a t s
26A/C-B7. 5Air conditioning system
27S/ROOF10Moon roof
28P/ S E AT F/ R30Po w e r s e a t s
29PSB30Pre-collision seat belt
30D/L-AM120Main body ECU
FuseAmpereCircuit
Page 749 of 908
749
ES350 300h_OM_OM33A01U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
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 probably
needs adjustment or repair. Contact your Lexus dealer as soon as pos-
sible.
Visible symptoms
Audible symptoms
Operational symptoms
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813
ES350 300h_OM_OM33A01U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
If your vehicle overheats (gasoline vehicles)
Follow the correction procedure as described below.Stop the vehicle in a safe place and turn off the air conditioning system,
and then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled
down sufficiently, inspect the
hoses and radiator core (radia-
tor) for any leaks.
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” line on the reservoir.
Reservoir cap
“FULL”
“LOW”
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 9 3 )
enters the red zone or a loss of engine power is experienced. (For
example, the vehicle speed does not increase.)
●Steam comes out from under the hood.
1
2
3
4
1
2
3
Page 814 of 908

8147-2. Steps to take in an emergency
ES350 300h_OM_OM33A01U_(U)
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditioning system on to check that
the radiator cooling fan operates and to chec k for coolant leaks from
the radiator or hoses.
The fan operates when the air conditioning system is turned on immediately after
a cold start. Confirm that the fan is operating by checking the fan sound and air
flow. If it is difficult to check these, tu rn the air conditioning system on and off
repeatedly.
(The fan may not operate in freezing temperatures.)
If the fan is not operating:
Stop the engine immediately and contact your Lexus dealer.
If the fan is operating:
Have the vehicle inspected at the nearest Lexus dealer.
5
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.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fan
and belts. Failure to do so may cause the hands or clothing to be caught, resulting
in serious injury.
●Do not loosen the radiator cap while the engine and radiator are hot.
High temperature steam or coolant could spray out.
6
7
Page 816 of 908
816
ES350 300h_OM_OM33A01U_(U)
7-2. Steps to take in an emergency
If your vehicle overheats (hybrid vehicles)
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place an d 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.
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. 9 3 )
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. 772) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3