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Total trailer weight Tongue load
Tongue load
Total trailer weight9 to 11%
(∗
1)
or 15% (∗
2)100 =
The trailer cargo load should be
distributed so that the tongue load
is 9 to 11% for weight carrying
hitch
(∗
1) or 15% for weight distrib-
ut i ng hi t ch (∗
2) of the total trailer
weight, not exceeding the maximum
load of the following.
Weight carrying hitch
Without towing package
90 kg (200 lb.)
With towing package
158 kg (350 lb.)
Weight distributing hitch
With towing package
238 kg (525 lb.)
Never load the trailer with more
weight in the back than in the
front. About 60% of the trailer load
should be in the front half of the
trailer and the remaining 40% in the
rear.
HITCHES
If you wish to install a trailer hitch, you
should consult with your Toyota dealer.
Use only a hitch recommended by the
hitch manufacturer and the one which
conforms to the total trailer weight
requirement.
The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer ’s instruc-
tions.
The hitch ball and king pin should have
a light coat of grease.
Toyota recommends removing the trail-
er hitch whenever you are not towing
a trailer to reduce the possibility of
additional damage caused by the hitch
if your vehicle is struck from behind.
After removing the hitch, seal any
mounting holes in the vehicle body to
prevent entry of pollutants such as ex-
haust fumes, dirt, water, etc.
NOTICE
Do not use axle−mounted hitches as
they can cause damage to the axle
housing, wheel bearings, wheels or
tires. Also, never install a hitch which
may interfere with the normal function
of an Energy Absorbing Bumper, if so
equipped.
BRAKES AND SAFETY CHAINS
Toyota recommends trailers with
brakes that conform to any applica-
ble federal and state/provincial regu-
lations.
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![TOYOTA SIENNA 1999 Owners Manual name. SIENNA (45403U)
203
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85F]) when going up a long or
steep grade with a TOYOTA SIENNA 1999 Owners Manual name. SIENNA (45403U)
203
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85F]) when going up a long or
steep grade with a](/manual-img/14/58486/w960_58486-202.png)
name. SIENNA (45403U)
203
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to ”If
your vehicle overheats” in Part 4 of
this manual.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in ”P”. Avoid park-
ing on a slope with a trailer, but if it
cannot be avoided, do so only after
performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un-
der both the vehicle and trailer wheels.
3. When the wheel blocks are in place,
release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into ”P” and turn off the engine.When restarting out after parking on a
slope:
1. With the transmission in ”P” position,
start the engine. Be sure to keep the
brake pedal depressed.
2. Shift into gear.
3. Release the parking brake and brake
pedal and slowly pull or back away
from the wheel blocks. Stop and apply
your brakes.
4. Have someone retrieve the blocks.
CAUTION
Do not exceed 72 km/h (45 mph) or
the posted towing speed limit,
whichever is lower. Because insta-
bility (swaying) of a towing vehicle−
trailer combination usually in-
creases as the speed increases, ex-
ceeding 72 km/h (45 mph) may
cause loss of control.
Slow down and downshift before
descending steep or long downhill
grades. Do not make sudden down-
shifts.
Avoid holding the brake pedal down
too long or too frequently. This
could cause the brakes to overheat
and result in reduced braking effi-
ciency.
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Checking brake fluid
To check the fluid level, simply look at
the see−through reservoir. The level
should be between the ”MAX” and
”MIN” lines on the reservoir.
It is normal for the brake fluid level to go
down slightly as the brake pads wear. So
be sure to keep the reservoir filled.
If the reservoir needs frequent refilling, it
may indicate a serious mechanical prob-
lem.
If the level is low, add SAE J1703 or
FMVSS No. 116 DOT 3 brake fluid to
the brake reservoir.
Remove and replace the reservoir cover
by hand.Use only newly opened brake fluid. Once
opened, brake fluid absorbs moisture from
the air, and excess moisture can cause a
dangerous loss of braking.
CAUTION
Take care when filling the reservoir
because brake fluid can harm your
eyes and damage painted surfaces. If
fluid gets in your eyes, flush your
eyes with clean water.
NOTICE
If you spill some of the fluid, be sure
to wash it off with water to prevent
it from damaging the parts or paint.
Checking power steering fluid
If hot
O.K.
If cold
O.K. Close
If hot
addIf cold
add Open
Check the fluid level through the reser-
voir. If necessary, add automatic trans-
mission fluid DEXRONII or III.
If the vehicle has been driven around 80
km/h (50 mph) for 20 minutes (a little
more in frigid temperatures), the fluid is
hot (60C—80C or 140F—175F). You
may also check the level when the fluid
is cold (about room temperature,
10C—30C or 50F—85F) if the engine
has not been run for about five hours.
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—Headlights
1. Open the hood. Unplug the connec-
tor. Remove the rubber cover.
If the connector is tight, wiggle it.2. Release the bulb retaining spring
and remove the bulb. Install a new
bulb and the bulb retaining spring.
To install a bulb, align the tabs of the
bulb with the cutouts of the mounting
hole.3. Install the rubber cover with the
”TOP” mark upward, and snuggle on
the boss. Then insert the connector.
Make sure the rubber cover fits snugly on
the connector and the headlight body.
Aiming is not necessary after replacing
the bulb. When aiming adjustment is nec-
essary, contact your Toyota dealer.
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21. ECU−IG 15 A: Cruise control system,
anti−lock brake system, locking with
wireless remote control system, theft
deterrent system
22. IGN 5 A: Gauges and meters, charging
system, SRS airbag system, seat belt
pretensioners, multiport fuel injection
system/sequential multiport fuel injec-
tion system
23. STOP 15 A: Stop lights, cruise control
system, high−mounted stoplight, tail
lights
24. TAIL 10 A: Parking lights, front side
marker lights, license plate lights, tail
lights
25. PWR−VENT 15 A: Power rear quarter
windows
26. OBD 7.5 A: On−board diagnosis sys-
tem
27. PWR−OUTLET 15 A: Power outlet
28. STARTER 5 A: Gauges and meters,
SRS airbag system, seat belt preten-
sioners, multiport fuel injection system/
sequential multiport fuel injection sys-
tem
29. DOOR 20 A: Power door lock system,
theft deterrent system30. PANEL 7.5 A: Gauge and meter, car
audio system, clock, air conditioning
system, instrument panel light control,
rear window defogger, electronically
controlled automatic transmission sys-
tem, emergency flashers, parking lights
31. TURN 7.5 A: Turn signal lights, emer-
gency flashers
32. RADIO NO.2 7.5 A: Car audio system
33. CIG 15 A: Cigarette lighter, clock, pow-
er rear view mirror controls, SRS air-
bag system, seat belt pretensioners,
back−up lights, theft deterrent system
34. A/C 5 A: Air conditioning system
35. A/F HTR 25 A: EFI system
Fuses (type B)
36. CDS FAN 40 A: Electric cooling fans
37. RDI FAN 40 A: Electric cooling fans
38. CDS FAN 30 A: Electric cooling fans
39. RDI FAN 30 A: Electric cooling fans
40. MAIN 40 A: ”DRL”, ”H−LP RH” and
”H−LP LH” fuses
41. R/R A/C 40 A: Rear air conditioning
system
42. HTR 50 A: Air conditioning system
43. DEF 30 A: Rear window defogger,
”MIRROR−HEATER” fuse44. AM1 40 A: ”INP” fuse
45. PWR 30 A: Power windows, electric
moon roof, power seat, power sliding
door, ”PWR−VENT” fuse
Fuses (type C)
46. ALT 140 A: Charging system, ”FL
ABS”, ”INP”, ”HTR” and ”R/R A/C”
fuses
47. INP 100 A: ”AM1” and ”DEF” fuses
48. FL ABS 60 A: Anti−lock brake system
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