Page 2249 of 4323
DIDAG±01
I28272
AVC±LAN:
Stereo Component
Amplifier Assy Radio Receiver Assy
(w/o Navigation)
Radio and Navigation Assy
(w/ Navigation)
Rear Seat Audio Controller
: AVC LAN
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2047
2241 Author: Date:
2005 SEQUOIA (RM1146U)
SYSTEM DESCRIPTION
1. OUTLINE
(a) Rear Seat Audio (RSA) system, which consists of a rear seat audio controller and a remote controller
(switch assy), enables the rear seat occupants to use headphones to listen simultaneously to a differ-
ent audio mode than the one that is selected in the front audio head unit.
2. COMMUNICATION SYSTEM
Page 2250 of 4323
DIDAI±01
Vehicle brought into a workshop
4. Check the diagnostic trouble codes
DTC is not output (Go to step 6)
5. Diagnostic trouble code chart
Go to step 7
7. Circuit inspection and part inspection
10. Perform confirmation test
ENDItems inside
are titles of pages in this manual,
with the page number in the bottom portion. See
the pages for detailed explanations.
P. DI±2053
P. DI±2058 ± DI±2076 P. DI±1979, DI±2203 1. Customer problem analysis
P. DI±2049
2. Problem Symptoms Confirmation
Symptom does
not occur
Malfunction
code
6. Problem symptoms table
P. DI±2050
8. Identification of problem
Symptom occursGo to step 4
3. Symptom Simulation
P. IN±24
9. Repair or replace
Normal system
code DI±2048
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2242 Author: Date:
2005 SEQUOIA (RM1146U)
HOW TO PROCEED WITH TROUBLESHOOTING
Page 2251 of 4323
DIDAJ±01
RSA SYSTEM Check Sheet
Inspector 's name:
Customer 's NameVIN
Production Date
Licence Plate No.
Odometer Reading / /km
mile
Frequency of Problem Occurrence / /
Constant Intermittent ( Times a day) Brought±in Date
Date of First Occurrence
Problem
Symptom
Headphone
DTC
Check
Parts name
DTC (1st time)DTC (2nd time) Switch Assy
Headphone Terminal Rear Seat Audio Controller Assy
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2049
2243 Author: Date:
2005 SEQUOIA (RM1146U)
CUSTOMER PROBLEM ANALYSIS CHECK
Page 2252 of 4323

DIDAK±01
DI±2050
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2244 Author: Date:
2005 SEQUOIA (RM1146U)
PROBLEM SYMPTOMS TABLE
RSA SYSTEM
SymptomSuspected AreasSee page
RSA system cannot be powered.1. Power source circuit (rear seat controller assy)DI±2058
Quality of sound from wireless headphone is poor or no sound
can be heard.
1. Power source circuit (rear seat controller assy)
2. Mute signal circuit (to rear seat audio controller)
3. Sound signal circuit (to rear seat audio controller)
4. Rear seat audio controllerDI±2058
DI±2066
DI±2070
±
Quality of sound from headphone connected to headphone termi-
nal is poor or no sound can be heard.
1. Power source circuit (rear seat controller assy)
2. Mute signal circuit (to rear seat audio controller)
3. Sound signal circuit (Rear seat audio controller ± head-
phone terminal)
4. Sound signal circuit (Radio receiver assy / radio and
navigation assy ± rear seat audio controller)DI±2058
DI±2066
DI±2073
DI±2070
REMOTE CONTROL
SymptomSuspected AreasSee page
A remote control system does not operate.
1. Power source circuit (rear seat controller assy)
2. A remote control system does not operate
3. AVC±LAN circuitDI±2058
DI±2076
DI±2061
Page 2253 of 4323

DIDAL±01
I28334
R24
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2051
2245 Author: Date:
2005 SEQUOIA (RM1146U)
TERMINALS OF ECU
1. REAR SEAT AUDIO CONTROLLER
Terminals No. (Symbols)Wiring ColorTerminal
DescriptionConditionSpecified value
R24±1 ± Body ground
(SGN1 ± Body ground)Shielded ±
Body groundGroundAlwaysBelow 1 V
R24±2 ± R24±17
(HP1L ± GND)BR ± LGSound signal
(Output)RSA system is sounding (Headphone)
A waveform syn-
chronized with
sounds is output
R24±3 ± R24±17
(HP1R ± GND)BR ± LGSound signal
(Output)RSA system is sounding (Headphone)
A waveform syn-
chronized with
sounds is output
R24±6 ± R24±17
(R±L± ± GND)W ± LGSound signal
(Input)RSA system is sounding
A waveform syn-
chronized with
sounds is output
R24±7 ± R24±17
(R±L+ ± GND)W ± LGSound signal
(Input)RSA system is sounding
A waveform syn-
chronized with
sounds is output
R24±8 ± R24±17
(R±R± ± GND)W ± LGSound signal
(Input)RSA system is sounding
A waveform syn-
chronized with
sounds is output
R24±9 ± R24±17
(R±R+ ± GND)W ± LGSound signal
(Input)RSA system is sounding
A waveform syn-
chronized with
sounds is output
R24±10 ± Body ground
(SG1 ± Body ground)Shielded ±
Body groundGroundAlwaysBelow 1 V
R24±11 ± R24±17
(RMUT ± GND)LG ± LGMute signalAudio system is playing " Changing modeAbove 3.5 V "
Below 1 V
R24±12 ± R24±17
(+B ± GND)LG ± LGBatteryAlways10 to 14 V
R24±13 ± Body ground
(SGN2 ± Body ground)Shielded ±
Body groundGroundAlwaysBelow 1 V
R24±14 ± R24±17
(HP2L ± GND)BR ± LGSound signal
(Output)RSA system is sounding (Headphone)
A waveform syn-
chronized with
sounds is output
R24±15 ± R24±17
(HP2R ± GND)BR ± LGSound signal
(Output)RSA system is sounding (Headphone)
A waveform syn-
chronized with
sounds is output
R24±17 ± Body ground
(GND ± Body ground)LG ±
Body groundGroundAlwaysBelow 1 W
Page 2254 of 4323

I28323
H10
H11
Headphone Terminal LH
Headphone Terminal RH DI±2052
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2246 Author: Date:
2005 SEQUOIA (RM1146U)R24±22 ±R24±17 (TX+ ±
GND)
LG ± LG
AVC±LAN
communication
signal
Ignition switch ON2 to 3 V
R24±23 ±R24±17 (TX± ±
GND)LG ± LG
AVC±LAN
communication
signal
Ignition switch ON2 to 3 V
R24±24 ± R24±17
(ACC ± GND)LG ± LGIgnition (ACC)Ignition switch ON10 to 14 V
2. HEADPHONE TERMINAL
Terminal No. (Symbols)Wiring ColorTerminal
DescriptionConditionSpecified value
H10±1 ± H10±3
(HPR ± SGND)BR ± ShieldedSound signal
(Input)External device system sounding
(At that time of headphone terminal use)A waveform syn-
chronized with
sound is output
H10±2 ± H10±3
(HPL ± SGND)BR ± ShieldedSound signal
(Input)External device system sounding
(At that time of headphone terminal use)A waveform syn-
chronized with
sound is output
H10±3 ± Body ground
(SGND ± Body ground)Shielded ± Body
groundGroundAlwaysBelow 1 V
H11±1 ± H11±3
(HPR ± SGND)BR ± ShieldedSound signal
(Input)External device system sounding
(At that time of headphone terminal use)A waveform syn-
chronized with
sound is output
H11±2 ± H11±3
(HPL ± SGND)BR ± ShieldedSound signal
(Input)External device system sounding
(At that time of headphone terminal use)A waveform syn-
chronized with
sound is output
H11±3 ± Body ground
(SGND ± Body ground)Shielded ± Body
groundGroundAlwaysBelow 1 V
Page 2255 of 4323

DIDAH±01
I28317
Switch Assy:
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
DI±2053
2247 Author: Date:
2005 SEQUOIA (RM1146U)
DTC CHECK / CLEAR
1. DIAGNOSIS CHECK
HINT:
RSA system inspects the devices consisting of Sub AVC±LAN
on the rear seat audio controller assy.
(a) Starting Main AVC±LAN (See page DI±1974, DI±2191).
HINT:
As starting Main AVC±LAN to operate the diagnosis
mode, Sub AVC±LAN also automatically enters the diag-
nosis mode. Perform the diagnosis mode operation on
the rear seat audio controller assy.
Use a switch assy to operate diagnosis mode.
(b) Service Check Screen
Reference
In the service check mode, the system check and
the diagnosis memory check are performed, and
the check results are displayed in ascending order
of the device codes (physical address).
TermsMeaning
Component code
(Physical address)Three±digit code (In hexadecimal) given to each device
comprising AVC±LAN. Corresponding to its function, individ-
ual symbol is provided.
Logical addressTwo±digit code (In hexadecimal) given to each function and
device unit in each device comprising AVC±LAN.
(c) Finishing Diagnosis Mode (See page DI±1974,
DI±2191).
(d) Element Check Mode
After the diagnosis start±up, the system enters the ele-
ment check mode. Check that the all elements come on.
Page 2256 of 4323

DI±2054
± DIAGNOSTICSREAR SEAT AUDIO SYSTEM
2248 Author: Date:
2005 SEQUOIA (RM1146U)
(e) Service Check Mode Result Display (for checking the cur-
rent and the past system conditions)
(1) Press the ºTUNE/TRACK UPº switch to see the
check result of each device.
(2) Check result display.
DisplayOriginal LanguageMeaningAction to be taken
goodGood (normal)No DTC is detected in both ºSystem Check Modeº and
ºDiagnosis Memory Modeº.±
NCONNo connection
The system recognized the component when it was regis-
tered, but the component gives no response to the ºDiagno-
sis Mode ON Requestº.
Check the power source cir-
cuit and the communication
circuit of the device indi-
cated by the device code
(physical address).
ECHNExchangeOne or more DTC for ºExchangeº is detected in either ºSys-
tem Check Modeº or ºDiagnosis Memory Modeº.
Go to the detailed informa-
tion mode to check the
trouble area by referring to
the DTC list.
CHECCheck
When no DTC is detected for ºExchangeº, one or more DTC
for ºCheckº is detected in either ºSystem Check Modeº or
ºDiagnosis Memory Modeº.Go to the detailed informa-
tion mode to check the
trouble area referring to the
DTC list.
I28309
The illustration shows the case that the system has 2 devices with codes 190 and 360, and the device (code
360) has a trouble.
The check result is displayed in ascending order of device code. The device code is displayed first, and then
the check result.P±±±indicates physical address
190±±±physical address
good±±±ºThe component is normalº.
P±±±indicates physical address
360±±±physical address
CHEC±±±ºCheck neededº.
: TUNE/TRACK UP
: TUNE/TRACK DOWN