2008 LEXUS RX400H cooling

357
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
24RDI FAN NO.240Electric cooling fan
25HAZ15Turn signal lights, emergency flashers
26MPX-B17. 5Electric power steering system
27AM2 NO.130“GAUGE NO.2”, “IGN”, “INJ” and
“ST” fuses
28HORN10Horns
29MAIN40
“H-LP L LWR”, “H-LP L UPR”, “H-LP
R LWR”, “H-LP R UPR” and “DRL”
fuses
30IGCT NO.150
“INV W/P”, “IGCT NO.2”, “IGCT
NO.3”, “IGCT NO.4” and “IGCT
NO.5” fuses
31RADIO NO.115Audio system
32ECU-B NO.17. 5
Theft deterrent system, air condition-
ing system, gauges and meters, moon
roof, multiplex communication system
33DOME7. 5
Personal lights, interior lights, vanity
lights, engine switch light, gauges and
meters, navigation system
34ECU-B NO.27. 5Wireless remote control
35AMP30Audio system
36DOOR NO.1 25Power door lock system
37A/F25Air/fuel control system
38CRT7. 5Navigation system screen, rear seat
entertainment system
39H-LP R LWR15Right-hand headlight (low beam)
40INV W/P15Hybrid system
FuseAmpereCircuit

361
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
65HEATER7. 5
Electric cooling fan, air conditioning
system, rear window defogger, engine
switch, windshield wiper de-icer
66WA S H E R20Windshield washer
67SEAT HTR20No circuit
68GAUGE NO.17. 5
Instrument cluster lights, instrument
panel lights, emergency flashers, seat
belt, power outlet, multiport fuel injec-
tion system/sequential multiport fuel
injection system, back-up lights
69FR WIP30Windshield wipers
70RR WIP15Rear window wiper
71INJ 20
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
72IGN10
SRS airbag system, multiport fuel
injection system/sequential multiport
fuel injection system, front passenger
occupant classification system, stop
lights, hybrid vehicle immobilizer sys-
tem
73GAUGE NO.27. 5Gauge and meters
74ECU-ACC7. 5
Navigation system display, power rear
view mirror control, shift lock control
system, multiplex communication sys-
tem
75CIG15Po w e r o u t l e t
76PWR OUTLET
NO.115Po w e r o u t l e t
FuseAmpereCircuit

5
When trouble arises
423
5-2. Steps to take in an emergency
RX400h_U
CAUTION
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling the battery.
●When working with the battery, always wear safety glasses and take care not to
allow any battery fluids (acid) to come into contact with skin, clothing or the vehi-
cle body.
●Do not lean over the 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 the battery support, terminals, and other
battery-related parts.
●Do not allow children near the battery.
NOTICE
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.

424
5-2. Steps to take in an emergency
RX400h_U
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message WATER TEMP is displayed on the multi-information
display.
■ Gasoline engine
If the needle of the engine coolant temperature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the hybrid system. Carefully lift the hood after the
steam subsides and then restart the hybrid system.
If you do not see steam: Leave the hybrid system running and carefully lift the hood.
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the temperature of the engine (shown on the
instrument cluste r) begins to fall and then stop the hybrid
system.
If the fan is not operating: Stop the hybrid system immediately and call your local
Lexus dealer.
After the hybrid system has
cooled down sufficiently, check
the engine coolant level and
inspect the radiator core (radia-
tor) for any leaks.
STEP1
STEP2
STEP3
STEP4

435
6-1. Specifications
6
Vehicle specifications
RX400h_U
Cooling system
Ignition system
Capacity
Gasoline engine
power control unit10.9 qt. (10.3 L, 9.0 Imp.qt.)
3.6 qt. (3.4 L, 3.0 Imp.qt.)
Coolant type
Use either of the following.• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili-cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life organic acid technology
Do not use plain water alone.
Spark plug
Make
DENSO
NGK
Gap
SK20R11
IFR6A11
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning the gasoline
engine.

473
Alphabetical index
RX400h_U
CareExterior ................................................... 298
Interior.......................................................301
Seat belts ............................................... 302
Cargo capacity ....................................... 178
Cargo hooks .......................................... 284
CD changer CD .............................................................. 214
MP3 disc ............................................... 220
WMA disc ............................................ 220
CD player.................................................. 214
Chains......................................................... 184
Child restraint system Booster seats, definition.................. 108
Booster seats, installation ..................113
Convertible seats, definition ......... 108
Convertible seats, installation .........113
Front passenger occupant
classification system .......................103
Infant seats, definition ....................... 108
Infant seats, installation........................113
Installing CRS with lower
anchorages ...........................................116
Installing CRS with seat belts ..........113
Installing CRS with top straps ........ 118
Child safety
Air bag precautions ............................ 98
Battery precautions.............. 328, 423
Child restraint system ...................... 108
Child-protectors................................... 40
How your child should wear the seat belt ...........................................62
Installing child restraints ..................... 112
Moon roof precautions ...................... 77
Power window lock switch .............. 72
Power window precautions............. 74 Removed rear seat entertainment
system controller battery............. 351
Removed wireless remote control battery precautions .......................349
Seat belt comfort guide .....................59
Seat belt extender precautions...... 64
Seat belt precautions .......................... 62
Seat heater precautions................. 280
Child-protectors ...................................... 40
Cleaning Exterior................................................... 298
Interior ...................................................... 301
Seat belts ................................................302
Clock ......................................................... 274
Coin holder .............................................268
Compass .................................................. 292
Condenser .............................................. 325
Console box ........................................... 266
Cooling system Engine overheating........................... 424
Cruise control Cruise control........................................157
Dynamic laser cruise control ........ 160
Cup holder .............................................. 269
Curtain shield airbags............................. 91
Customizable features .......................458
Daytime running light system ........... 149
Defogger Rear window ........................................204
Side mirror.............................................204
Dimension................................................430
Dinghy towing ......................................... 196
Display
Dynamic laser cruise control ........ 160
Trip information ................................... 146C
D