ECU LEXUS RX400H 2008 Owner's Guide

307
4-2. Maintenance
4
Maintenance and care
RX400h_U
Vehicle interior
ItemsCheck points
Accelerator pedal• Moves smoothly (without uneven pedal effort or catching)?
Transmission “Park” mechanism
• Can the vehicle be hold securely on an incline with the shift lever in
P?
Brake pedal
• Moves smoothly?
• Does it have appropriate clearance and correct amount of free play?
Brakes
• Not pull to one side when applied?
• Loss of brake effectiveness?
• Spongy feeling brake pedal?
• Pedal almost touches floor?
Head restraints• Move smoothly and lock securely?
Indicators/buzzers•Function properly?
Lights
• Do all the lights come on?
• Headlights aimed correctly? (→ P. 364)
Pa r k i n g b r a ke
• Moves smoothly?
• Can hold the vehicle securely on
an incline?
Seat belts
• Does the seat belt system operate smoothly?
• Are the belts undamaged?
Seats• Do the seat controls operate prop- erly?

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

360
4-3. Do-it-yourself maintenance
RX400h_U
57RR FOG 7. 5No circuit
58AIR SUS7. 5No circuit
59DOOR NO.225Multiplex communication system
60S/ROOF 30Moon roof
61TA I L10
Front fog lights, instrument cluster
lights, instrument panel lights, front
side marker lights, tail lights, license
plate lights, towing converter
62PA N E L7. 5
Glove box light, instrument cluster
lights, instrument panel lights, console
box light, audio system, power outlet,
garage door opener switch, transmis-
sion system, headlight cleaner, seat
heaters, steering switches, power
back door
63ECU-IG NO.17. 5
Power rear view mirror control, moon
roof, multiplex communication system,
shift lock control system, multiplex
communication system (power door
lock system, wireless remote control
system), driving position memory sys-
tem, vehicle dynamics integrated
management, windshield wipers,
transmission, seat heaters, power
seats, tilt and telescopic steering,
power back door
64ECU-IG NO.210
Automatic headlight leveling system,
vehicle dynamics integrated manage-
ment, dynamic laser cruise control,
headlight cleaner, adaptive front-light-
ing 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

375
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
CAUTION
■Replacing light bulbs
●Turn off the headlights. Do not attempt to replace the bulb immediately after turn-
ing off the headlights.
The bulbs become very hot and may cause burns.
●Do not touch the glass portion of the light bulb with bare hands. Hold the bulb by
the plastic or metal portion.
If the bulb is scratched or dropped it may blow out or crack.
●Fully install light bulbs and any parts used to secure them.
Failing to do so may result in heat damage, fire, or water entering the headlight
unit. This may damage the headlights or cause condensation to build up on the
lens.
●Do not attempt to take apart or repair the low beam discharge headlight bulbs,
connectors, power supply circuits, or related components.
Doing so could result in electric shock and serious injury or death.
■Discharge headlights
●Contact your Lexus dealer before replacing discharge headlights (including light
bulbs).
●Do not touch the high-intensity discharge headlight’s high voltage socket when
the headlights are turned on.
An extremely high voltage of 20000 V will be discharged and could result in
serious injury or death by electric shock.
■To prevent damage or fire
Make sure bulbs are fully seated and locked.

378
RX400h_U
5-1. Essential information
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The hybrid system is running, but the vehicle will not move.
● The vehicle makes an abnormal sound.
Emergency towing
If a tow truck is not available, in an emergency your vehicle may be tem-
porarily towed using a cable or chain secured to the emergency towing
eyelet(s). This should only attempted on hard, surfaced roads for short
distances at low speeds.
A driver must be in the vehicle to steer and operate the brakes. The vehi-
cle’s wheels, drive train, axles, steer ing and brakes must be in good condi-
tion.
Towing eyelets
If towing is necessary, we recommend having your vehicle towed by your
Lexus dealer or a commercial towing se rvice, using a lift-type truck or a flat
bed truck.
Use a safety chain system for all towing, and abide by all state/provincial
and local laws.
If towing from the front, the vehicle’s rear wheels and axles must be in good
condition. ( →P. 3 8 2 )
If they are damaged, use a towing dolly or flat bed truck.

380
5-1. Essential information
RX400h_U
Installing towing eyeletsRemove the eyelet cover.
Insert the towing eyelet into the
hole and tighten partially by hand.
Tighten down the towing eyelet
securely using a wheel nut wrench.
STEP1
STEP2
STEP3
■Location of the emergency towing eyelet
→P. 4 0 8

5
When trouble arises
381
5-1. Essential information
RX400h_U
Towing with a sling-type truck
CAUTION
■Installing towing eyelets to the vehicle
Make sure that towing eyelets are installed securely.
If not securely installed, towing eyelets may come loose during towing. This may
lead to accidents that cause serious injury or even death.
NOTICE
■To prevent body damage
Do not tow with a sling type truck, either from the front or rear.

5
When trouble arises
393
5-2. Steps to take in an emergency
RX400h_U
■Key reminder buzzer
The buzzer indicates that the key has not been removed from the engine switch
(with the engine switch in the ACC or LOCK position and the driver’s door
opened).
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).

5
When trouble arises
415
5-2. Steps to take in an emergency
RX400h_U
Stowing the flat tire, jack and all toolsInstall the inside spare tire cover on the outer side of the spare tire
cover. Put the flat tire in the spare tire
cover with the outer side facing up
and install the holding bracket.
Turn the spare tire clamp bolt clockwise with a jack handle and
adapter socket until you hear a click.
Stow all the tools and jack securely.
STEP1
STEP2
■After completing the tire change
The tire pressure warning system must be reset. ( →P. 3 3 2 )
STEP3
STEP4