2001 TOYOTA SEQUOIA navigation system

I28599I28773
w/ Navigation:
Radio and Navigation AssyRear Seat Audio Controller
R27
Stereo Component Amplifier AssyTX± TX+
S10 ID2
LG
LG
V
P L 9
10
5
1522
R24
23
TX± TX+
ATX± ATX+27 26
TX± TX+ 20
19 R30LGID2 R24
S10 R30 R27
DI±2062
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2256 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Service check mode (Rear seat audio controller).
CHECK:
Start the diagnosis system and read the check result for the rear seat audio controller (See page DI±1974,
DI±2191).
RESULT:
ºNCONº is displayed or result is not displayed (w/ naviga-
tion)Go to step A
ºNCONº is displayed or result is not displayed (w/o naviga-
tion)Go to step B
ºNCONº is displayed or result is not displayed (DSP AMP)Go to step C
ºGOODº is displayedGo to step D
B Go to step 3.
C Go to step 4.
D Replace radio and navigation assy or radio re-
ceiver assy.
A

I28299TX±
Radio and Navigation Assy
Wire Harness View:
TX+R27
I28337TX+
R24
TX±
Rear Seat Audio Controller
Wire Harness View:
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2063
2257 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check harness and connector (Rear seat audio controller ± Radio and navigation
assy).
PREPARATION:
Disconnect the R24 and R27 connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol
(Tester connection)ConditionSpecified condition
TX+ (R24±22) ±
TX+ (R27±9)AlwaysBelow 1 W
TX± (R24±23) ±
TX± (R27±10)AlwaysBelow 1 W
TX+ (R24±22) ± Body
groundAlways10 kW or higher
TX± (R24±23) ± Body
groundAlways10 kW or higher
NG Repair or replace harness or connector.
OK
Replace rear seat audio controller.

I28606
Radio Receiver Assy
Wire Harness View:
TX±
TX+
R4
I28292TX+
Radio and Navigation Assy:
TX±R30
I28752
Stereo Component Amplifier Assy :
S10
TX± TX+
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2065
2259 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check harness and connector (Radio receiver assy / radio and navigation assy ±
Stereo component amplifier assy).
PREPARATION:
Disconnect the radio receiver assy or radio and navigation assy
and stereo component amplifier assy connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Radio Receiver Assy:
Symbol
(Tester connection)ConditionSpecified condition
TX+ (R4±5) ±
TX+ (S10±20)AlwaysBelow 1 W
TX± (R4±15) ±
TX± (S10±19)AlwaysBelow 1 W
TX+ (R4±5) ± Body
groundAlways10 kW or higher
TX± (R4±15) ± Body
groundAlways10 kW or higher
Radio And Navigation Assy:
Symbol
(Tester connection)ConditionSpecified condition
TX+ (R30±5) ±
TX+ (S10±20)AlwaysBelow 1 W
TX± (R30±15) ±
TX± (S10±19)AlwaysBelow 1 W
TX+ (R30±5) ± Body
groundAlways10 kW or higher
TX± (R30±15) ± Body
groundAlways10 kW or higher
NG Repair or replace harness or connector.
OK
Replace rear seat audio controller.

I28377
w/o Navigation System:
R19
Radio Receiver AssyRear Seat Audio Controller
RMUT
ID2 19
R2411
RMU11
LG R±W
I28377
w/ Navigation System:
R27
Radio and Navigation AssyRear Seat Audio Controller
RMUT
ID2 19
R2411
RMUT11
LG R±W DI±2066
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2260 Author: Date:
2005 SEQUOIA (RM1146U)
Mute signal circuit (to rear seat audio controller)
CIRCUIT DESCRIPTION
This circuit sends the signal to the rear seat audio controller to mute the noise. Because of that, the noise
produced by changing the sound source ceases.
If there is an open in the circuit, noise can be heard from the speaker when changing the sound source.
If there is a short in the circuit, even though the rear seat audio controller is normal, no sound or only extreme-
ly small sound can be produced.
WIRING DIAGRAM
DIDAO±01

I28336
RMUT
R24Wire Harness View:
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2067
2261 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect rear seat audio controller.
PREPARATION:
Make sure that the rear seat audio controller connector is con-
nected.
CHECK:
Measure the voltage according to the value in the table below.
OK:
Symbol
(Tester connection)ConditionSpecification
RMUT (R24±11) ±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±2050).
NG
2 Check system.
CHECK:
Check whether the vehicle is equipped with a navigation system or not.
RESULT:
w/o NavigationGo to step A
w/ NavigationGo to step B
B Go to step 5.
A

I28337
R24
RMUT
Rear Seat Audio Controller
Wire Harness View:
I28299RMU
Radio and Navigation Assy
Wire Harness View:
R27
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2069
2263 Author: Date:
2005 SEQUOIA (RM1146U)
5 Check harness and connector (Radio and navigation assy ± Rear seat audio con-
troller).
PREPARATION:
Disconnect the R24 and R27 connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol
(Tester connection)ConditionSpecified condition
RMUT (R24±11) ±
RMU (R27±19)AlwaysBelow 1 W
RMUT (R24±11) ± Body
groundAlways10 kW or higher
NG Repair or replace harness or connector.
OK
6 Replace rear seat audio controller.
CHECK:
Replace the rear seat audio controller and check if it operates normally.
OK:
The function returns to normal.
OK Normal operation.
NG
Replace radio and navigation assy.

I28600
w/ Navigation System:
Radio and Navigation AssyRear Seat Audio Controller
R±R+
ID2 15
9
W W R27
R±R± 16
R248
W G
R±L+ 17
R247
W B
R±L± 18
R24
W
R
SG1 14
R24106 9
8
7
106 R±R+
R±R±
R±L+
R±L±
RSLD
(Shielded)
(Shielded) ID2
ID2
ID2
ID2R24
R27
R27
R27
R27 DI±2070
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2264 Author: Date:
2005 SEQUOIA (RM1146U)
Sound signal circuit (Radio receiver assy / radio and navigation
assy ± rear seat audio controller)
CIRCUIT DESCRIPTION
The radio receiver assy (radio and navigation assy) sends a sound signal to the rear seat audio controller
through this circuit.
The sound signal that has been sent is amplified by the stereo component amplifier assy, and then sent to
the speaker.
If there is an open or short in the circuit, sound can not be heard from the speaker even if there is no malfunc-
tion in the rear seat audio controller or speaker.
WIRING DIAGRAM
DIDAP±01

I28600
w/o Navigation System:
Radio Receiver Assy
Rear Seat Audio Controller
R±R+
ID2 15
R249
W W R19
R±R± 16
R248
W G R19
R±L+ 17
R247
W B R19
R±L± 18
R24
W
R R19
SG1 14
R2410
R196 9
8
7
106 RSR+
RSR±
RSL+
RSL±
SLD1
(Shielded)
(Shielded) ID2
ID2
ID2
ID2
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2071
2265 Author: Date:
2005 SEQUOIA (RM1146U)