2001 TOYOTA SEQUOIA brake light

± BODY ELECTRICALTROUBLESHOOTING
BE±5
3409 Author: Date:
2005 SEQUOIA (RM1146U) Taillight does not go off when light control switch is in OFF posi-
tion.
1. TAILLIGHT Relay
2. Light Control Switch
3. Wire Harness
4. Body ECUBE±27
BE±27
±
±
Headlight does not come on when engine is running and light
control switch is in OFF position .
1. ECU±B Fuse
2. MAIN Fuse
3. HEAD Relay
4. DRL Fuse
5. DRL No. 4 Relay
6. DIMMER Relay
7. Parking Brake Switch
8. Wire Harness
9. Body ECUBE±14
BE±14
BE±27
BE±14
BE±27
BE±55
BE±55
±
±
FOG LIGHT 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
Fog light does not come on with light control switch is in HEAD
position.
(Headlight is normal.)
1. FOG Fuse
2. FOG LIGHT Relay
3. Fog Light Switch
4. Wire Harness
5. Body ECUBE±14
BE±27
BE±34
±
±
Fog light does not come on with light control switch is in HEAD
position.
(Headlight does not light).1.*1 Other Parts
2. Wire Harness±
±
Only one light does not come on.1. Bulb
2. Wire Harness±
±
*1: Inspect Headlight System
TURN SIGNAL AND HAZARD WARNING SYSTEM
SymptomSuspect AreaSee page
ºHazardº and ºTurnº do not light up.
1. GAUGE Fuse
2. TURN±HAZ Fuse
3. Ignition Switch
4. Turn Signal Flasher Relay
5. Wire HarnessBE±14
BE±14
BE±24
BE±24
±
Hazard warning light does not light up.
(Turn is normal)1. Hazard Warning Switch
2. Wire Harness
3. Turn Signal Flasher RelayBE±36
±
BE±36
Turn signal does not light up.
(Hazard is normal)1. Turn Signal Switch
2. Wire Harness
3. Turn Signal Flasher RelayBE±36
±
BE±36
Turn signal does not light up in one direction.1. Bulb
2. Wire Harness±
±
Only one bulb does not light up.1. Bulb
2. Wire Harness±
±
INTERIOR LIGHT 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
All the interior lights do not come on.
1. DOME Fuse
2. Illumination Circuit
3. Body ECUBE±14
DI±1759
±

± 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
±

BE17A±06
I28425
Brake Master Cylinder

Brake Fluid Level Warning Switch
Engine Room R/B

ECU±B Fuse
Light Control Rheostat
Combination Meter Assembly
Instrument Panel J/B

IGN 2 Fuse

GAUGE Fuse
Parking Brake SwitchIgnition Switch
Passenger Seat Belt Warning
Skid Control ECU
± BODY ELECTRICALCOMBINATION METER
BE±53
3457 Author: Date:
2005 SEQUOIA (RM1146U)
COMBINATION METER
LOCATION

I01279
Warning Light
Ignition
Switch
Battery
I19428
21OFF
ON
N01212
BE1217
Warning Light
Ignition
Switch
Battery
± BODY ELECTRICALCOMBINATION METER
BE±57
3461 Author: Date:
2005 SEQUOIA (RM1146U)
7. INSPECT BRAKE WARNING LIGHT OPERATION
(a) Disconnect the connector from the brake fluid warning
switch.
(b) Release the parking brake pedal.
(c) Connect the terminals on the harness side of the level
warning switch connector.
(d) Start the engine and check that the warning light comes
on.
If the warning light does not come on, test the bulb or wire har-
ness.
8. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CONTINUITY
(a) Remove the reservoir tank cap and strainer.
(b) Disconnect the connector.
(c) Check that no continuity exists between the terminals with
the switch OFF (float up).
(d) Use siphon, etc. to drain fluid out of the reservoir tank.
(e) Check that continuity exists between the terminals with
the switch ON (float down).
(f) Pour the fluid back in the reservoir tank.
If continuity is not as specified, replace the switch.
9. INSPECT PARKING BRAKE SWITCH CONTINUITY
(a) Check that continuity exists between the terminal and
switch body with the switch ON (switch pin released).
(b) Check that no continuity exists between the terminal and
switch body with the switch OFF (switch pin pushed in).
If operation is not as specified, replace the switch or inspect
ground point.
10. INSPECT WASHER LEVEL WARNING LIGHT OPERA-
TION
(a) Disconnect the connectors from the combination meter.
(b) Connect the negative (±) lead from the battery to terminal
16.
(c) Turn the ignition switch ON and check that the warning
light comes on.
If the warning light does not come on, test the bulb.

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.

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.

BO47P±01
BO0632
BO0633
15°
45°
± BODYSEAT BELT
BO±161
3714 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION
CAUTION:
Replace the seat belt assembly (outer belt, inner belt, bolts,
nuts or sill±bar) if it has been used in a severe impact. The
entire assembly should be replaced even if damage is not
obvious.
1. RUNNING TEST (IN SAFE AREA)
(a) Fasten the front seat belts.
(b) Drive the car at 10 mph (16 km/h) and slam on the brakes.
Check that the belt locks and cannot be extended at this
time.
HINT:
Conduct this test in a safe area. If the belt does not lock, remove
the belt mechanism assembly and conduct the following static
check. Also, whenever installing a new belt assembly, verify the
proper operation before installation.
2. Driver 's seat belt (ELR):
STATIC TEST
(a) Make sure that the belt locks when pulled out quickly.
(b) Remove the locking retractor assembly.
HINT:
Before removing the pretensioner connector, be sure to read
the precautionary notice in the RS section.
(c) Tilt the retractor slowly.
(d) Make sure that the belt can be pulled out at a tilt of 15 de-
grees or less, and cannot be pulled out over 45 degrees
of tilt.
If a problem is found, replace the assembly.
3. Except driver's seat belt (ELR/ALR):
STATIC TEST
(a) Make sure that the belt locks when pulled out quickly.
(b) Pull out the whole belt, then retract the belt slightly and
pull it out again
(c) Make sure that the belt cannot be extended further.
If a problem is found, replace the assembly.
(d) Remove the locking retractor assembly.
HINT:
Front passenger's seat belt only:
Before removing the pretensioner connector, be sure to read
the precautionary notice in the RS section.
(e) Tilt the retractor slowly.

05_SEQUOIA_U (L/O 0408)
10
2005 SEQUOIA from Aug. '04 Prod. (OM34424U)
or
Driver 's seat belt reminder light*
1
Discharge warning light*
1
Low fuel level warning light*
1
Brake system warning light*
1
Malfunction indicator lamp*
1
Anti±lock brake system warning light*
1
Automatic transmission fluid temperature
warning light (four±wheel drive models)*
1
SRS warning light*
1
Open door warning light*
1
Low windshield washer fluid level warning
light*
1
Front passenger 's seat belt reminder light*
1
Vehicle stability control system/traction control
system (two±wheel drive models) or active
traction control system (four±wheel drive
models) warning light
*
1
Low tire pressure warning light*
1
Engine oil replacement reminder light*
1
Indicator symbols on the instrument panel