2008 Lexus GX470 air suspension

179
2-5. Driving information
2
When driving
NOTICE
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealer.
This is because the removal and attachment of snow tires affects the operation of
the tire pressure warning valves and transmitters.
■When jacking up or installing tire chains
Be sure to turn off the rear height control air suspension and stop the engine.
Otherwise, the vehicle height may change because of the automatic leveling func-
tion, resulting in an accident.
■Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly when
tire chains are fitted.

183
2-5. Driving information
2
When driving
Connecting trailer lightsUse the wire harness stored in the rear end underbody.
■When connecting and disconnecting a trailer
Connecting Set the rear height control air suspension to “LO” mode.
Turn off the engine switch or the rear height control air suspension.
Connect the trailer.
Turn on the switch that was turned off on STEP 2.
Set the rear height control air suspension to “N” mode.
Disconnecting Set the rear height control air suspension to “LO” mode.
Turn off the engine switch or the rear height control air suspension.
Set the supporting leg of the trailer on the ground and raise the hitch by
4 in. (100 mm).
Turn on the switch that was turned off on STEP 2.
Wait until vehicle height is stabilized.
Make sure the hitch is disconnected. If the hitch does not disconnect, raise
the hitch higher and repeat steps 2 through 5.
Move the vehicle forward in the “LO” mode where the hitch does not
touch anything in the “N” mode.
Set the rear height control air suspension in the “N” mode.
STEP1STEP1
STEP2STEP2
STEP1STEP3STEP3
STEP1STEP4STEP4
STEP1STEP5STEP5STEP5
STEP1STEP1
STEP2STEP2
STEP1STEP3STEP3
STEP1STEP4STEP4
STEP1STEP5STEP5STEP5
STEP1STEP5STEP6STEP6STEP6
STEP1STEP5STEP6STEP7STEP7
STEP1STEP5STEP6STEP8STEP8

185
2-5. Driving information
2
When driving
CAUTION
■To avoid accident or injury
●The total trailer weight (trailer weight plus the weight of cargo) must not exceed
6500 lb. (2948 kg).
●If a trailer and cargo weight over 2000 lb. (907 kg), use a sway control device
with sufficient capacity.
●The gross combined weight (sum of your vehicle weight plus its load and the total
trailer weight) must not exceed 12000 lb. (5443 kg).
●Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle
weight and trailer tongue load capacities.
●Never load more weight in the back than in the front of the trailer. About 60% of
the load should be in the front half of the trailer, and the remaining 40% in the
rear.
●Set the vehicle height to the “LO” mode and turn off the rear height control air
suspension to prevent the vehicle he ight from automatically changing.
●The tow hitch receiver installed on your vehicle must never be used on another
vehicle
■Hitches
●If you wish to install a trailer hitch, contact your Lexus dealer.
●Use only a hitch that conforms to the total trailer weight requirement.
●Follow the directions supplied by the hitch manufacturer.
●Lubricate the hitch ball with a light coat of grease.
●Remove the trailer hitch whenever you are not towing a trailer. After removing
the hitch, seal any mounting hole in the vehicle body to prevent entry of any sub-
stances into the vehicle.
■When towing a trailer
●If the total trailer weight exceeds 1000 lb . (453 kg), trailer brakes are required.
●Never tap into your vehicle’s hydraulic system, as this will lower the vehicle’s brak-
ing effectiveness.
●Never tow a trailer without using a safety chain securely attached to both the
trailer and the vehicle. If damage occurs to the coupling unit or hitch ball, there is
danger of the trailer wandering into another lane.

357
4-3. Do-it-yourself maintenance
4
Maintenance and care
Fuse layout and amperage ratings■ Engine compartment
FuseAmpereCircuit
1ALT140
Charging system, AM1, HEATER,
CDS FAN, FR FOG, DEFOG, AIR
SUS, AC INV, SEAT HEATER, OBD,
STOP, J/B, RR AC, MIR HEATER,
BATT CHG, TOWING BRK, TOW-
ING
2HEATER50Air conditioning system
3AIR SUS50Rear height control air suspension
4AM150
ACC, CIG, IG1, FR WIP-WSH, RR
WIP, RR WSH, DIFF, ECU-IG,
TEMS, STA
5TOWING BRK30Trailer brake controller
6J/B50
P FR P/W, P RR P/W, D RR P/W, D
P/ S E AT, P P/ S E AT, TA I L , PA N E L ,
POWER OR TI&TE
7BATT CHG30Trailer sub battery

358
4-3. Do-it-yourself maintenance
FuseAmpereCircuit
8TOW I N G40Trailer lights
9CDS FAN20Electric cooling fan
10RR A/C30Rear air conditioning system
11MIR HEATER10Outside rear view mirror defogger
12STOP10
Stop lights, high mounted stoplight,
shift lock control system, vehicle sta-
bility control system, electronic mod-
ulated suspension, rear height control
air suspension, multiport fuel injec-
tion system/sequential multiport fuel
injection system
13AC INV15Power outlet (115V AC)
14FR FOG15Front fog lights
15OBD7. 5On-board diagnosis system
16HEAD (LO RH)10Right hand headlight (low beam)
17HEAD (LO LH)10Left hand headlight (low beam)
18HEAD (HI RH)10Right hand headlight (high beam)
19HEAD (HI LH)10Left hand headlight (high beam)
20EFI NO.210
Multiport fuel injection system/
sequential multiport fuel injection
system
21HEATER No.27. 5Air conditioning system
22DEFOG30Rear window defogger
23AIRSUS NO.210Rear height control air suspension
24S E AT H E AT E R20Seat heaters

361
4-3. Do-it-yourself maintenance
4
Maintenance and care
■Driver’s side instrument panel
FuseAmpereCircuit
1IGN10
Multiport fuel injection system/
sequential multiport fuel injection
system, vehicle stability control sys-
tem
2SRS10SRS airbag system, front passenger
occupant classification system
3GAUGE7. 5Gauges and meters
4ST27. 5
Multiport fuel injection system/
sequential multiport fuel injection
system
5FR WIP-WSH30Windshield wipers, windshield
washer
6TEMS20Electronic modulated suspension
7DIFF20Four-wheel drive system
8RR WIP15Rear window wiper
9D P/SEAT30Driver’s power seat
10P P/SEAT30Front passenger’s power seat
11PWR OUTLLET15Po w e r o u t l e t ( 1 2 V D C )

5
When trouble arises
373
5-1. Essential information
Towing eyelets
■Emergency towing procedureRelease the parking brake.
Put the shift lever in “N”.
The engine switch must be in the “ACC” position (engine off) or the “ON”
position (engine on).
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelet and the cable or chain.
●If the engine is not running, the power assi st for the brakes and steering will not
function, making steering and braking more difficult.
●Put the vehicle height in the “N” (normal) mode and push the height control
“OFF” switch to turn off rear height co ntrol air suspension. Otherwise the auto-
matic leveling function may adjust the vehicle height unexpectedly, resulting in an
accident.
NOTICE
■To prevent causing serious damage to the transmission
Never tow this vehicle from the rear with four wheels on the ground.
STEP1
STEP2
STEP3

5
When trouble arises
377
5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temper ature gauge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● 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, sp ongy feeling, pedal almost touches
the floor