2001 TOYOTA SEQUOIA ECU

DIDC4±01
I28763
R27
R29R30
R26R28
± DIAGNOSTICSNAVIGATION SYSTEM
DI±2187
2381 Author: Date:
2005 SEQUOIA (RM1146U)
TERMINALS OF ECU
1. RADIO AND NAVIGATION ASSY
Symbols (Terminal No.)Wiring ColorTerminal DescriptionConditionSpecification
ACC (R30±11) ±
GND (R30±20)GR ± BRAccessory (ON)Ignition switch OFF
"ACC or ONBelow 1 V "10 to 14 V
B (R30±1) ± GND (R30±20)L±Y ± BRBatteryAlways10 to 14 V
GND (R30±20) ± Body groundBR ±
Body groundGroundAlwaysBelow 1 V
ANT (R30±13) ±
GND (R30±20)B±R ± BRPower source of antennaRadio switch ON and AM or FM10 to 14 V
ILL+ (R30±2) ± ILL± (R30±12)G ± W±GIllumination signal
Ignition switch ON
Light control switch OFF "TAIL or
ONBelow 1 V "
10 to 14 V
R+ (R30±8) ± GND (R30±20)W ± BRSound signal (Right)Audio system is playing
A waveform synchro-
nized with sound is out-
put
L+ (R30±9) ± GND (R30±20)B ± BRSound signal (Left)Audio system is playing
A waveform synchro-
nized with sound is out-
put
R± (R30±18) ± GND (R30±20)G ± BRSound signal (Right)Audio system is playing
A waveform synchro-
nized with sound is out-
put
L± (R30±19) ± GND (R30±20)R ± BRSound signal (Left)Audio system is playing
A waveform synchro-
nized with sound is out-
put
SWG (R27±6) ± Body groundBR±W ±
Body groundSteering pad switch
groundAlwaysBelow 1 V
SW1 (R27±7) ± SWG (R27±6)LG±R ± BR±WSteering pad switch signal
Steering pad switch not operated
"SEEK+ switch pushed
"SEEK± switch pushed
"VOL+ switch pushed
"VOL± switch pushed4 V or more
"Approx. 0.5 V
"Approx. 0.9 V
"Approx. 2.0 V
"Approx. 3.4 V

± DIAGNOSTICSNAVIGATION SYSTEM
DI±2209
2403 Author: Date:
2005 SEQUOIA (RM1146U)E2
ON/OFF indication parameter
errorWhen the command for ON/OFF control from the
master device has a problem.Replace radio and navigation assy.±
E3
*1Registration demand transmis-
sion
When the registration demand command from the
slave device is output, or when the registration
demand command is output by receiving connec-
tion confirmation command from the sub master
device.
NOTE: This DTC may not be directly related to
the problem.
±±
E4
*1Multiple frame incomplete
When the multiple frame transmission ends in-
complete.
NOTE: This DTC may not be directly related to
the problem.
±±
HINT:

*1: This code may be recorded depending on the battery condition or engine start voltage even if no
failure is detected.

*2: This code may be stored if the ignition key is turned to the START position again with the engine
running.

*3: This code may be stored if the ignition key is held in the START position for 1 minute or more before
returning to the ON position.

*4: If the device is reported as not existing during verification, check the power source circuit and AVC±
LAN circuit for the device.

*5: w/ Rear seat audio system only.

*6: w/ Rear seat entertainment system only.
3. Multi±display controller sub±assy (Physical address: 1F6) [RSE ECU, MAIN]
(a) Logical address: 01 (Communication control)
DTCNameDiagnosisVerificationSee page
21ROM ErrorAbnormal condition of ROM is detected.Replace multi±display controller
sub±assy.±
22ROM ErrorAbnormal condition of RAM is detected.Replace multi±display controller
sub±assy.±
D1
*1
*4Registered component discon-
nected
AVC±LAN transmitting abnor-
malitiesComponent shown by sub±code is or was discon-
nected from system with ignition switch in ACC or
ON.
Communication with component shown by sub±
code is not ensured when engine is started.
1. Power source circuit (Multi±dis-
play controller sub±assy).
2. AVC±LAN (Radio and navigation
assy ± Multi±display controller
sub±assy).
3. Replace Multi±display controller
sub±assy.DI±2110
DI±2139
±
D7
*2AVC±LAN Communication
Check Error
Component in which this code is recorded is or
was disconnected from system after engine start.
Or, when recording this code, multi±display con-
troller was disconnected.
1. Power source circuit (radio and
navigation assy).
2. Power source circuit (Multi±dis-
play controller sub±assy).
3. AVC±LAN (Radio and navigation
assy ± Multi±display controller
sub±assy).
4. Replace Multi±display controller
sub±assy.DI±2256
DI±2110
DI±2139
±
D6
*1Absence of Master
Component in which this code is recorded has
been disconnected from system with ignition in
ACC or ON. Or, when this code was recorded,
multi±display controller was disconnected.
1. Power source circuit (radio and
navigation assy).
2. AVC±LAN (Radio and navigation
assy ± Multi±display controller
sub±assy).
3. Replace Multi±display controller
sub±assy.DI±2256
DI±2139
±

I28255
DI±2226
± DIAGNOSTICSNAVIGATION SYSTEM
2420 Author: Date:
2005 SEQUOIA (RM1146U)
3 Inspect radio and navigation assy.
PREPARATION:
Remove the antenna plug from the radio and navigation assy.
CHECK:
With the radio and navigation assy connector connected, turn
the ignition switch to the ACC position.
Turn on the radio and choose the AM mode.
Place a screwdriver or a piece of metal such as thin wire on an
antenna jack of the radio and navigation assy and check that
the noise is heard from the speaker.
OK:
Noise occurs.
NG Replace radio and navigation assy.
OK
4 Check antenna assy.
CHECK:
Check that the antenna is securely installed.
OK:
The antenna is installed properly.
NG Install antenna assy properly.
OK

DI±2230
± DIAGNOSTICSNAVIGATION SYSTEM
2424 Author: Date:
2005 SEQUOIA (RM1146U)
5 Check using another CD.
CHECK:
Check using another CD.
Check if the problem recurs using another CD.
OK:
The problem does not recur.
OK Replace CD.
NG
Proceed to next circuit inspection shown in problem symptoms table (See page DI±2184).

± DIAGNOSTICSNAVIGATION SYSTEM
DI±2233
2427 Author: Date:
2005 SEQUOIA (RM1146U)
Abnormal noise occurs
INSPECTION PROCEDURE
1 Check 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 only excessively loud noise. If loud noise
occurs, check that all wiring is proper and that the antenna installation part ground and noise±prevention
equipment are installed.
Conditions under 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 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 is 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 continues even after the engine
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 relevant part.

First ensure that the noise is not coming from outside. Failure to do so makes noise source detection
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±2174).
DIDCO±01

± DIAGNOSTICSNAVIGATION SYSTEM
DI±2235
2429 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check using another CD.
CHECK:
Check if the problem recurs using another CD.
OK:
The problem does not recur.
OK Replace CD.
NG
4 Check radio and navigation assy.
CHECK:
Check that the radio and navigation assy is properly installed.
OK:
Radio and navigation assy is properly installed.
NG Reinstall radio and navigation assy properly.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±2184).

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

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