2001 TOYOTA SEQUOIA Page 18

DI±2000
± DIAGNOSTICSAUDIO SYSTEM
2194 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
NOTICE:
The vehicle is equipped with SRS (Supplemental Restraint System) such as airbags. Before servic-
ing (including removal or installation of parts), be sure to read the precautionary notice for the sup-
plemental restraint system (See page RS±1).
1 Check illumination.
CHECK:
Check if the illumination for the radio receiver assy, steering pad switch assy or others (A/C switch, cigarette
lighter, etc.) comes on when the light control switch is turned to the HEAD or TAIL position.
RESULT:
Components with illuminationGo to step
Illumination comes on for all components except radio receiver assy.A
Illumination comes on for all components except steering pad switch does not
come on.B
Illumination comes on for all components except radio receiver assy, steering
pad switch, Rear heater control panel, each switch, etc.C
All illumination does not come on. (Radio receiver assy, steering pad switch,
Combination meter, Rear heater control panel, each switch, etc.)D
HINT:
If the illuminations have malfunctions, check the rheostat switch.
B Go to step 4.
C Go to step 8.
D Go to combination meter system
(See page DI±1645).
A

I28755
Stereo Component Amplifier Assy:
MUTE
S10
I28606
Radio Receiver Assy
Wire Harness View:
MUTE
R4
I28752
Stereo Component Amplifier Assy:
MUTE
S10
± DIAGNOSTICSAUDIO SYSTEM
DI±2009
2203 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect stereo component amplifier assy.
PREPARATION:
Make sure that the stereo component amplifier assy connector
is connected.
CHECK:
Measure the voltage according to the value in the table below.
OK:
Symbol
(Tester connection)ConditionSpecification
MUTE (S10±1) ±
Body groundTurn ignition switch to
ACC, Audio system is
playing "Changing mode
Above 3.5 V " Below 1 V
OK Proceed to next circuit inspection shown in
problem symptoms table (See page DI±1967).
NG
2 Check harness and connector (Radio receiver assy ± Stereo component amplifi-
er assy).
PREPARATION:
Disconnect the radio receiver assy and stereo component am-
plifier assy connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol
(Tester connection)ConditionSpecified condition
MUTE (R4±7) ±
MUTE (S10±1)AlwaysBelow 1 W
MUTE (R4±7) ±
Body groundAlways10 kW or higher
NG Repair or replace harness or connector.

I28739
Radio Receiver Assy
Wire Harness View:
R4
L±
L+ R+ R±
I28752
Stereo Component Amplifier Assy
Wire Harness View:
L+
R±L±
R+
S10
DI±2012
± DIAGNOSTICSAUDIO SYSTEM
2206 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check harness and connector (Radio receiver assy ± Stereo component amplifi-
er assy).
PREPARATION:
Disconnect the radio receiver assy and stereo component am-
plifier assy connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol (Tester connection)Specified condition
L+ (R4±9) ± L+ (S10±3)Below 1 W
L± (R4±19) ± L± (S10±2)Below 1 W
R+ (R4±8) ± R+ (S10±5)Below 1 W
R± (R4±18) ± R± (S10±4)Below 1 W
L+ (R4±9) ± Body ground10 kW or higher
L± (R4±19) ± Body ground10 kW or higher
R+ (R4±8) ± Body ground10 kW or higher
R± (R4±18) ± Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±1967).

± DIAGNOSTICSAUDIO SYSTEM
DI±2019
2213 Author: Date:
2005 SEQUOIA (RM1146U)
5 Inspect rear speaker assy.
CHECK:
Measure the resistance between the terminals of the speaker.
NOTICE:
The speaker should not be removed for checking.
OK:
2.6 ± 0.2 W
NG Replace rear speaker assy.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±1967).

DI±2022
± DIAGNOSTICSAUDIO SYSTEM
2216 Author: Date:
2005 SEQUOIA (RM1146U)
9 Inspect rear speaker assy.
CHECK:
Measure the resistance between the terminals of the speaker.
NOTICE:
The speaker should not be removed for checking.
OK:
Approximately 4 W
NG Replace rear speaker assy.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±1967).

I28739
Radio Receiver Assy
Wire Harness View:
TX±
TX+
R4
I28752
Stereo Component Amplifier Assy:
TX± TX+
S10
± DIAGNOSTICSAUDIO SYSTEM
DI±2025
2219 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check harness and connector (Radio receiver assy ± Stereo component amplifi-
er assy).
PREPARATION:
Disconnect the stereo component amplifier assy connector.
CHECK:
Measure the resistance according to the values in the table be-
low.
OK:
Symbol (Tester connection)Specified condition
TX+ (R4±5) ± TX+ (S10±20)Below 1 W
TX± (R4±15) ± TX± (S10±19)Below 1 W
TX+ (R4±5) ± Body ground10 kW or higher
TX± (R4±15) ± Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown on problem symptoms table or diagnostic trouble code
chart (See page DI±1967 or DI±1979).

± DIAGNOSTICSAUDIO SYSTEM
DI±2027
2221 Author: Date:
2005 SEQUOIA (RM1146U)
Noise occurs
INSPECTION PROCEDURE
1 Check of speaker installation.
CHECK:
Check if each speaker is securely installed.
OK:
Each speaker is securely installed.
HINT:
The radio is equipped with a noise prevention system that blocks excessively loud noise. If such noise oc-
curs, check the all wiring is proper and that the antenna installation part ground and noise±prevention equip-
ment are installed.
Condition in which noise occursNoise type
Noise increases when the accelerator pedal is depressed, but stops when
the engine is stopped.Generator noise
Noise occurs during A/C or the heater operation.Blower motor noise
Noise occurs when the vehicle accelerates rapidly on an unpaved road or
after the ignition switch is turned on.Fuel pump noise
Noise occurs when the horn switch is pressed and released or when pressed
and held.Horn noise
Quiet noise occurs while the engine is running, but stops when the engine is
stopped.Ignition noise
Noise occurs synchronously with the blink of the turn signal.Flasher noise
Noise occurs during window washer operation.Washer noise
Noise occurs while the engine is running, and it continues even after the en-
gine is stopped.Water temperature sensor noise
Noise occurs during wiper operation.Wiper noise
Noise occurs when the brake pedal is depressed.Stop light switch noise
Others.Static electricity stored on the vehicle
HINT:

Identify the condition under which the noise occurs, and check the noise filter on the related part.

First ensure that the noise is not coming from the outside. Failure to do so makes noise source detec-
tion difficult and may lead to a misdiagnosis.

Noise should be removed in descending order of loudness.
NG Install it properly.
OK
Identification of noise source (See page DI±1964).
DIDA3±01

DIDAD±01
DI±2044
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2238 Author: Date:
2005 SEQUOIA (RM1146U)
REAR SEAT AUDIO SYSTEM
PRECAUTION
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