Page 51 of 4323

MA003±50
MA±4
± MAINTENANCEUNDER HOOD
51 Author: Date:
2005 SEQUOIA (RM1146U)
UNDER HOOD
GENERAL MAINTENANCE
1. GENERAL NOTES
Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.
Every service item in the periodic maintenance schedule must be performed.
Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).
Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.
Failure to do even one item can cause the engine to run poorly and increase exhaust emissions.
2. WINDSHIELD WASHER FLUID
Check that there is sufficient fluid in the tank.
3. ENGINE COOLANT LEVEL
Check that the coolant level is between the FULL and LOW lines on the see±through reservoir.
4. RADIATOR AND HOSES
(a) Check that the front of the radiator is clean and not blocked with leaves, dirt or bugs.
(2UZ±FE engine: See page CO±14)
(b) Check the hoses for cracks, kinks, rot or loose connections.
5. BATTERY ELECTROLYTE LEVEL
Check that the electrolyte level of all battery cells is between the upper and lower level lines on the case.
6. BRAKE AND CLUTCH FLUID LEVELS
Check that the brake and clutch fluid levels are near the upper level line on the see±through reservoirs.
7. ENGINE DRIVE BELTS
Check all drive belts for fraying, cracks, wear or oiliness.
8. ENGINE OIL LEVEL
Check the level on the dipstick with the engine turned off.
9. POWER STEERING FLUID LEVEL
(a) Check the level on the dipstick.
(b) The level should be in the HOT or COLD range depending on the fluid temperature.
10. AUTOMATIC TRANSMISSION FLUID LEVEL
(a) Park the vehicle on a level surface.
(b) With the engine idling and the parking brake applied, shift the selector into all positions from the P to
L, and then shift into the P position.
(c) Pull out the dipstick and wipe off the fluid with a clean rag. Re±insert the dipstick and check that the
fluid level is in the HOT range.
(d) Do this check with the fluid at normal driving temperature (70 ± 80°C, 158 ± 176°F).
HINT:
Wait until the engine cools down (approx. 30 min.) before checking the fluid level after extended driving at
high speeds, in hot weather, in heavy traffic or pulling a trailer.
11. EXHAUST SYSTEM
(a) Visually inspect for cracks, holes or loose supports.
(b) If any change in the sound of the exhaust or smell of the exhaust fumes is noticed, find the cause and
correct.
Page 897 of 4323
DIDCB±01
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±695
889 Author: Date:
2005 SEQUOIA (RM1146U)
AIR SUSPENSION SYSTEM
PRECAUTION
Be sure to switch the height control mode select switch to manual mode and cancel the auto leveling
function when:
Jacking up the vehicle.
A trailer etc. is attached to the vehicle.
NOTICE:
When disconnecting the battery terminal, initialize the following system after the terminal is recon-
nected.
System NameSee Page
Back Door Power Window Control SystemBE±77
Page 3425 of 4323
± BODY ELECTRICALTROUBLESHOOTING
BE±13
3417 Author: Date:
2005 SEQUOIA (RM1146U)
BACK DOOR POWER WINDOW CONTROL SYSTEM
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
SymptomSuspect AreaSee page
Back door power window does not operate.
1. Back Door Power Window Motor Circuit
2. Window Pulse Sensor Circuit
3. Rear Wiper Motor Circuit
4. Back Door Control Light Switch Circuit
5. Back Door ECU
6. Body ECUIN±35
DI±1877
DI±1880
DI±1864
±
±
TRAILER TOWING
SymptomSuspect AreaSee page
Trailer towing does not operate.
1. TOWING Fuse
2. TOWING TAIL Fuse
3. TOWING BRK Fuse
4. TOWING TAIL Relay
5. BATT CHARGE Relay
6. Towing Converter Relay
7. Brake Controller
8. Wire HarnessBE±14
BE±14
BE±14
BE±148
BE±148
BE±148
BE±148
±
Page 3559 of 4323
BE26G±04
I28424
Engine Room J/B
TOWING Fuse
Trailer Socket
Towing Converter Relay
(Located inside of the quarter trim panel LH)
Engine Room R/B No. 3
BATT CHARGE Relay
TOWING TAIL Relay
TOWING BRK Fuse
TOWING TAIL Fuse
Brake Controller
(Located inside of the cowl side trim board LH)
± BODY ELECTRICALTRAILER TOWING
BE±147
3551 Author: Date:
2005 SEQUOIA (RM1146U)
TRAILER TOWING
LOCATION
Page 3560 of 4323

BE2D5±02
I24381
Wire Harness Side: BE±148
± BODY ELECTRICALTRAILER TOWING
3552 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION
1. INSPECT TOWING CONVERTER CIRCUIT
Remove the towing converter with the connector still connected
and inspect the wire harness side connector from the back side,
as shown in the table below.
Tester connectionConditionSpecified condition
4 ± 6Turn signal switch LEFT or hazard warning switch ON10 ± 14 V e 0 V
4 ± 6Turn signal switch LEFT and stop light switch ON (Brake pedal depressed)10 ± 14 V e 0 V
4 ± 6Turn signal switch OFF, hazard warning switch OFF and stop light switch OFF
(Brake pedal released)0 V
4 ± 6Stop light switch ON (Brake pedal depressed)10 ± 14 V
6 ± 9Turn signal switch LEFT or hazard warning switch ON10 ± 14 V e 0 V
6 ± 9Turn signal switch OFF or RIGHT and hazard warning switch OFF0 V
6 ± Body groundAlwaysContinuity
2 ± 6Turn signal switch RIGHT or hazard warning switch ON10 ± 14 V e 0 V
2 ± 6Turn signal switch RIGHT and stop light switch ON (Brake pedal depressed)10 ± 14 V e 0 V
26Turn signal switch OFF, and hazard warning switch OFF and stop light switch OFF0V2 ± 6Turn signal switch OFF, and hazard warning switch OFF and sto light switch OFF
(Brake pedal released)0 V
2 ± 6Stop light switch ON (Brake pedal depressed)10 ± 14 V e 0 V
1 ± 6Always10 ± 14 V
6 ± 8Stop light switch ON (Brake pedal depressed)10 ± 14 V
6 ± 8Stop light switch OFF (Brake pedal released)0 V
3 ± 6Turn signal switch RIGHT or hazard warning switch ON10 ± 14 V e 0 V
3 ± 6Turn signal switch OFF or LEFT and hazard warning switch OFF0 V
If the circuit is not as specified, inspect the circuit connected to
other parts.
Page 3561 of 4323

I24379
Wire Harness Side:
I18635
1
2 34
5
I18635
1
2 34
5
± BODY ELECTRICALTRAILER TOWING
BE±149
3553 Author: Date:
2005 SEQUOIA (RM1146U)
2. Trailer Socket 7 Pin Type:
INSPECT BRAKE CONTROLLER CIRCUIT
Remove the brake controller with the connector still connected
and inspect the wire harness side connector from the back side,
as shown in the table below.
Tester connectionConditionSpecified condition
1 ± 3Stop light switch ON (Brake pedal depressed)10 ± 14 V
1 ± 3Stop light switch OFF (Brake pedal released)0 V
2 ± 3Always10 ± 14 V
3 ± 4Stop light switch ON (Brake pedal depressed)10 ± 14 V
3 ± 4Stop light switch OFF (Brake pedal released)0 V
3 ± 5Light control switch TAIL or HEAD10 ± 14 V
3 ± 5Light control switch OFF0 V
If the circuit is not as specified, inspect the circuit connected to
other parts.
3. INSPECT TOWING TAIL RELAY CONTINUITY
ConditionTester connectionSpecified condition
Always1 ± 2Continuity
Always3 ± 5No continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
4. INSPECT BATT CHARGE RELAY CIRCUIT
ConditionTester connectionSpecified condition
Always1 ± 2Continuity
Always3 ± 5No continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
Page 4018 of 4323

05_SEQUOIA_U (L/O 0408)
159
2005 SEQUOIA from Aug. '04 Prod. (OM34424U)
Idling for a long period with the air
conditioning on in stop±and±go traffic.
Towing a trailer.
NOTICE
Do not remove the thermostat in
the engine cooling system as this
may cause the engine to overheat.
The thermostat is designed to con-
trol the flow of coolant to keep the
temperature of the engine within
the specified operating range.
Do not continue driving with an
overheated engine. See ªIf your ve-
hicle overheatsº on page 386 in
Section 4.
Normal
driving
Idling
The oil pressure gauge indicates engine
oil pressure when the ignition switch is
on. Check it while driving to make sure
that the needle is in the proper range.
If the oil pressure should stay below the
normal range, pull off the road to a safe
place and stop the engine immediately.
Call a Toyota dealer or qualified repair
shop for assistance.
Oil pressure may not build up when the
oil level is too low. The oil pressure
gauge is not designed to indicate oil level,
and the oil level must be checked using
the level dipstick.
NOTICE
Do not drive the vehicle with the oil
pressure below the normal range until
the cause is fixedÐit may ruin the
engine.
Oil pressure gauge
Page 4036 of 4323

05_SEQUOIA_U (L/O 0408)
177
2005 SEQUOIA from Aug. '04 Prod. (OM34424U)
If the automatic unlocking operation linked
to shift lever position is set, all doors are
automatically unlocked when the selector
lever is moved to ªPº position after the
ignition switch is turned to ªONº position.
For details, see ªÐAutomatic door locking
and unlocking functionsº on page 27 in
Section 1±2.
(i) Good driving practice
If the transmission repeatedly shifts up
and down between fourth gear and
overdrive when climbing a gentle slope,
the overdrive should be turned off. Be
sure to turn the switch on immediately
afterward.
When towing a trailer, in order to main-
tain engine braking efficiency, do not
use overdrive.
CAUTION
Always keep your foot on the brake
pedal while stopped with the engine
running. This prevents the vehicle
from creeping.
NOTICE
Always use the brake pedal or the
parking brake to hold the vehicle on
an upgrade. Do not attempt to hold
the vehicle using the accelerator ped-
al, as this can cause the transmission
to overheat.
Front drive control switches
Center differential lock switch
Four±wheel drive systemÐ
(a) Front drive control