Page 717 of 908

ES350 300h_OM_OM33A01U_(U)
7176-3. Do-it-yourself maintenance
6
Maintenance and care
22EFI NO.3
10*2Multiport fuel injection system, sequential
multiport fuel system, air intake system,
exhaust system
7. 5*1Multiport fuel injection system, sequential
multiport fuel system, air intake system
23INJ7. 5Multiport fuel injection system, sequential
multiport fuel system
24ECU-IG2 NO.37. 5
Multiport fuel injection system, sequential
multiport fuel system, electronic controlled
transmission, power management system,
steering lock system, cruise control system
25IGN15Starting system
26D/L-AM225Power door lock system
27IG2-MAIN25INJ, IGN
28ALT-S*27. 5Charging system
DC/DC-S*17. 5Hybrid system
29MAYDAY5MAYDAY
30TURN&HAZ15Turn signal lights, emergency flashers
31STRG LOCK10Steering lock system
32AMP30Audio system
33H-LP LH-LO15Left-hand headlight
34H-LP RH-LO15Right-hand headlight
35EFI-MAIN NO.130EFI NO.2, EFI NO.3, fuel system
36SMART5Smart access system with push-button start,
occupant classification system
37ETCS10Multiport fuel injection system, sequential
multiport fuel system
38ABS NO.2*17. 5VSC, ABS
39EFI NO.17. 5
Multiport fuel injection system, sequential
multiport fuel system, electronic controlled
transmission
FuseAmpereCircuit
Page 718 of 908
718
ES350 300h_OM_OM33A01U_(U)
6-3. Do-it-yourself maintenance
*1:Hybrid vehicles
*2: Gasoline vehicles
40
A/F*220Air intake system
EFI-MAIN
NO.2
*120Fuel system, air intake system, exhaust sys-
tem
41AM27. 5Power management system, smart access
system with push-button start
42PA N E L10
Switch illumination, audio system, multi-infor-
mation display, audio display, shift lever light,
glove box light, console box light, Remote
Touch, intuitive parking assist switch illumina-
tion
43DOME7. 5Clock, footwell lights, vanity lights, ornament
lights, personal lights, door courtesy lights
44ECU-B NO.110
Smart access system with push-button start,
main body ECU, steering sensor, gauges and
meters, gateway ECU, electric tilt and tele-
scopic steering column, power seats, over-
head module, outside mirror control ECU,
power trunk opener and closer ECU
45SPARE25Spare fuse
46SPARE30Spare fuse
FuseAmpereCircuit
Page 719 of 908
ES350 300h_OM_OM33A01U_(U)
7196-3. Do-it-yourself maintenance
6
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
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 722 of 908
722
ES350 300h_OM_OM33A01U_(U)
6-3. Do-it-yourself maintenance
31TI&TE20Electric tilt and telescopic steering column
32A/B10Occupant classification system, SRS airbag
system
33ECU-IG2 NO.17. 5Gauges and meters
34ECU-IG2 NO.27. 5
VSC, ABS, gateway ECU, smart access sys-
tem with push-button start, SRS airbag sys-
tem
35CIG& P/OUTLET15Po w e r o u t l e t
36ECU-ACC7. 5Main body ECU, gauges and meters, outside
rear view mirrors
37ECU-IG1 NO.310
Intuitive parking assist, driver support sys-
tem, skid control buzzer, Blind Spot Monitor,
radar sensor
38S/HTR RR20No circuit
FuseAmpereCircuit
Page 723 of 908

ES350 300h_OM_OM33A01U_(U)
7236-3. Do-it-yourself maintenance
6
Maintenance and care
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may need
replacement. (P. 7 2 4 )
●If the replaced fuse blows again, have the vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you use genuine Lexu s products designed for this vehicle.
Because certain bulbs are connected to circuits designed to prevent overload, non-
genuine parts or parts not designed for this vehicle may be unusable.
CAUTION
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage rating than that indicated, or use any
other object in place of a fuse.
●Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
●Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Lexus
dealer as soon as possible.
Page 797 of 908

797
ES350 300h_OM_OM33A01U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
If the engine will not start (gasoline vehicles)
One of the following may be the cause of the problem:
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●The engine may be flooded.
Try to restart the engine again foll owing correct starting procedures.
( P. 1 9 7 )
●There may be a malfunction in the engine immobilizer system.
( P. 8 0 )
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( P. 805)
●The 12-volt battery terminal connecti ons may be loose or corroded.
The engine starting system may be malfunctioning due to an electrical
problem such as electronic key ba ttery depletion or a blown fuse. How-
ever, an interim measure is available to start the engine. ( P. 7 9 8 )
If the engine will not start even though correct starting procedures are
being followed ( P. 197), consider each of the following points:
The engine will not start even though the starter motor operates
normally.
The starter motor turns over slowly, the interior lights and head-
lights are dim, or the horn does not sound or sounds at a low vol-
ume.
The starter motor does not turn over