Page 2457 of 4323
I28261
± DIAGNOSTICSNAVIGATION SYSTEM
DI±2255
2449 Author: Date:
2005 SEQUOIA (RM1146U)
Speed signal error
INSPECTION PROCEDURE
1 Navigation check mode (Vehicle sensors check).
CHECK:
(a) Enter the ºNavigation Checkº mode (Vehicle Sensors)
(See page DI±2180).
(b) While driving, compare the ºSPDº indicator to the reading
on the speedometer. Check if these readings are almost
the same.
OK:
The readings are almost the same.
OK Replace radio and navigation assy.
NG
Proceed to next circuit inspection shown in diagnostic trouble code chart (See page DI±2203).
DIDD9±01
Page 2458 of 4323
I28474
11 Radio and
Navigation Assy
ACC
1
20
GND GR 1
RAD No. 24 3 A36
ACC Cut Relay
P
3
1 AM1 ACC12 Sub J/B No. 3
3A
W±R
W±R1
IA1 24
L±Y L±Y
2B
3
2C8
2D1 Engine Room J/B
RAD No. 1
ECU±BShort Pin 1J3
1EW±R
1L1
1C6AM12
ALT
B
Battery
IOBRR30 3A
I18
Ignition SWW±LB 212 1
1C 1FGR
GRB C B±O
J37To ECM
J38
Instrument Panel J/B
1 2B
R30
R30 J/C
PW W±R
B 8
54F10
FL Block DI±2256
± DIAGNOSTICSNAVIGATION SYSTEM
2450 Author: Date:
2005 SEQUOIA (RM1146U)
Power source circuit (Radio and navigation assy)
CIRCUIT DESCRIPTION
This circuit provides power to the radio and navigation assy.
WIRING DIAGRAM
DIDDB±01
Page 2459 of 4323
I28292
B
GND
ACC
R30
± DIAGNOSTICSNAVIGATION SYSTEM
DI±2257
2451 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect radio and navigation assy (B, ACC, GND).
PREPARATION:
Disconnect the radio and navigation assy connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol
(Tester connection)ConditionSpecified condition
GND (R30±20) ±
Body groundAlwaysBelow 1 W
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Symbol
(Tester connection)ConditionSpecified condition
B (R30±1) ±
GND (R30±20)Always10 to 14 V
ACC (R30±11) ±
GND (R30±20)Ignition switch is in ACC10 to 14 V
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in problem symptoms table or diagnostic trouble code
chart (See page DI±2203 or DI±2184).
Page 2460 of 4323
I28475
GR 1
4 3 A36
ACC Cut Relay
12 Sub J/B No. 3
3AW±R 1
2 3A
GRB C B±O
J37To ECM
J38
RAD No. 2
3
1 6AM1 212 1Instrument Panel J/B
1 2
P
3AM1
ACC W±R
W±L
ALT
B
Battery W±RIL12
L±W
2A
2C8
2D1 Engine Room J/B
RAD No. 3
ECU±BShort Pin 3
B B
BBJ11
J10 J11 L±W
IOBR
BRS10
S9
S9S9
S9 12
10
15
161ACC
B2+
B+
GND
E Stereo Component
Amplifier Assy
1J 1E
1L 1C 1C 1FJ/C
J/C
B
1GR
L±W
L±W
W±R
I18
Ignition SW P
W
8
4
5F10
FL Block DI±2258
± DIAGNOSTICSNAVIGATION SYSTEM
2452 Author: Date:
2005 SEQUOIA (RM1146U)
Power source circuit (Stereo component amplifier assy)
CIRCUIT DESCRIPTION
This circuit provides power to the stereo component amplifier assy.
WIRING DIAGRAM
DIDDD±01
Page 2461 of 4323
I28324
ACC
EB+
B2+
GND
S10S9
± DIAGNOSTICSNAVIGATION SYSTEM
DI±2259
2453 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect stereo component amplifier assy (B+, B2+, ACC, GND, E).
PREPARATION:
Disconnect the stereo component amplifier assy connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Symbol
(Tester connection)ConditionSpecified condition
E (S9±16) ± Body groundAlwaysBelow 1 W
GND (S9±15) ±
Body groundAlwaysBelow 1 W
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Symbol
(Tester connection)ConditionSpecified condition
B+ (S9±1) ± GND (S9±15)Always10 to 14 V
B2+ (S9±10) ±
GND (S9±15)Always10 to 14 V
ACC (S10±12) ±
GND (S9±15)Ignition SW ACC10 to 14 V
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in problem symptoms table or diagnostic trouble code
chart (See page DI±2203 or DI±2184).
Page 2462 of 4323
I28766
R6
Light Control
Rheostat AssyRadio and Navigation Assy
J/C
Steering Pad Switch Assy
Spiral Cable
Sub±assy From
TAILLIGHT
RelayILL±
SWG J/C
ILL+ W±G
GJ39 J40
J39 J40
J39 J40W±G
G
G
G A B
A
AAB
ILL±
T12
2
6 1
10C9±1
BR±W
C9±10 6
4
Steering SWR30
R27 R30 DI±2260
± DIAGNOSTICSNAVIGATION SYSTEM
2454 Author: Date:
2005 SEQUOIA (RM1146U)
Illumination circuit
CIRCUIT DESCRIPTION
Power is supplied to the radio and navigation panel illumination when the light control switch is in the TAIL
or HEAD position. The body ECU determines the external brightness based on the brightness level detected
by the automatic light control sensor, and then operates the TAILLIGHT relay. Power can also be supplied
by operating the relay.
The intensity of the radio receiver panel illumination can be adjusted by the rheostat switch.
WIRING DIAGRAM
DIDDF±01
Page 2463 of 4323

± DIAGNOSTICSNAVIGATION SYSTEM
DI±2261
2455 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 and navigation 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 and navigation assy.A
Illumination comes on for all components except steering pad switch.B
Illumination comes on for all components except radio and navigation assy,
steering pad switch, Rear heater control panel, each switch, etc.C
All illumination does not come on. (Radio and navigation 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
Page 2464 of 4323
I28747
R30
ILL+
DI±2262
± DIAGNOSTICSNAVIGATION SYSTEM
2456 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check radio and navigation assy (ILL+).
PREPARATION:
Disconnect the radio and navigation assy connector.
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Symbol
(Tester connection)ConditionSpecified condition
ILL+ (R30±2) ±
Body groundLight control switch TAIL10 to 14 V
NG Repair or replace wire harness or connector
(Radio and navigation assy ± battery).
OK