I07735
± BODY ELECTRICALAUDIO SYSTEM
BE±191
2492 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. DIAGNOSIS FUNCTION (PIONEER made)
Error codes over tuner and connected equipment are displayed on the screen of tuner.
(a) Diagnosis start±up
For shifting to diagnosis mode, push ºCDº switch 3 times with pressing º1º and º6º of PRESET switch
at the same time while the audio power is OFF and ACC is ON.
To exit from diagnosis mode, press ºCDº switch for 2 seconds or turn the ignition key OFF.
(When º1±190º is displayed, the mode is transferred to LAN check mode.)
(b) LAN check
When starting up the diagnosis mode, the mode turns to LAN check mode, the screen displays the
code numbers (physical address) of tuner and connected equipment. Smaller codes are displayed in
order, displayed code numbers are switched by operating TUNE ºUPº or ºDOWNº switch. In LAN check
mode, by pressing º5º of PRESET switch for more than 2 secs., diagnosis memory of each equipment
can be deleted, when deletion is completed, the mode returns to LAN check mode.
Code No. (physical address) List
Code No. (physical address)Equipment name
190Radio receiver assembly (Audio head unit)
240CD changer (in Luggage room)
360CD changer (in center console and glove compartment box)
440Power amplifier
(c) System check
When pressing º1º of PRESET switch in LAN check mode, the mode turns to the system check
mode, the system performs self diagnosis of connected equipment and displays the re-
sults.(ºSYSº (showing the system is under detection) is displayed.)
Perform the operation shown in the following illustration, then read the result of the inspection.
H: This shows the equipment has a diagnosis code.
190: Physical address
1: This is the number allotted to the diagnosis code
that occurred.
21: DTC No.
Last Code No.: NO DTC No.
Pressing TURN ºDOWNº
Pressing TURN ºUPº
.
.
..
.
.1: This is the number allotted to the diagnosis code
that occurred. BE±192
± BODY ELECTRICALAUDIO SYSTEM
2493 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HINT:
It sometimes takes approx. 40 secs. till the system inspection is completed.
The chart below is an example of when diagnosis code º21º appears on the physical address (190)
equipment. (ROM error occurs on the radio receiver.)
The smaller code numbers (physical address) are displayed in order (code No., diagnosis code, sup-
port code of diagnosis code (object equipment)).
When no error is detected in the system, º00º is displayed.
When an error code is detected, up to 6 codes per one system are displayed. Pressing TUNE ºUPº
or ºDOWNº switches the display.
In the system check mode, when pressing º6º of PRESET switch the mode returns to LAN check mode.
(d) Diagnosis memory
(1) In LAN check mode, when pressing º2º of PRESET switch the mode turns to the diagnosis
memory mode. (ºCODEº is displayed.)
The results of self diagnosis performed over tuner and connected equipment are memorized and
displayed.
(2) Perform the operation shown in the following illustration, then read the result of the inspection.
HINT:
The smaller code numbers (physical address) are displayed in order (code No. , periodic communica-
tion number when error occurs, diagnosis code, and support code of diagnosis code (object equip-
ment)).
When no error is detected in the system, º00º is displayed. When an error code is detected, up to 6
codes per one system are displayed. Pressing TUNE ºUPº or ºDOWNº switches the display. Each diag-
nosis code is same as code in the system check mode.
When pressing º6º of PRESET switch, the mode returns to LAN check mode.
The following illustration below is an example of when diagnosis code ºD1º appears on the code (190)
and (240 or 360) equipment. (Communication error occurs between the radio receiver and CD chang-
er.)
H: This shows the equipment has a diagnosis code.
190: Physical address
1: This is the number allotted to the diagnosis code
that occurred.
Last Code No.
.
.
..
.
.
06: Periodic communication number of when
occurring in the diagnosis memory code.
Pressing TURN ºDOWNºPressing TURN ºUPº
21: Periodic communication number of when
occurring in the diagnosis memory code.
1: This is the number allotted to the diagnosis code
that occurred.
d1: DTC No.
1: This is the number allotted to the diagnosis code
that occurred.
360: Physical address
(Equipment that is communicating code)
± BODY ELECTRICALAUDIO SYSTEM
BE±193
2494 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(e) Diagnosis memory clear
(1) After error is fixed, start up the diagnosis mode.
(2) Continue pressing preset switch º5º for 2 secs. (CLr is displayed.)
(3) Press the preset switch º2º and transfer to the diagnosis memory mode and check that the normal
code (00) is output.
BE0GC±05
BE±196
± BODY ELECTRICALAUDIO SYSTEM
2497 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
TROUBLESHOOTING
NOTICE:
When replacing the internal mechanism (computer part) of the audio system, be careful that no part
of your body or clothing comes in contact with the terminals of the leads from the IC, etc. of the re-
placement part (spare part).
HINT:
This inspection procedure is a simple troubleshooting which should be carried out on the vehicle during sys-
tem operation and was prepared on the assumption of system component troubles (except for the wires and
connectors, etc.).
Always inspect the trouble taking the following items into consideration.
Open or short circuit of the wire harness
Connector or terminal connection fault
For audio systems with anti±theft system, troubleshooting items marked ( * ) indicate that ºTrou-
bleshooting for ANTI±THEFT SYSTEMº should be carried out first.
ProblemNo.
RadioRadio not operating when power switch turned to 'ON'.1
Display indicates when power switch turned to 'ON', but no sound (including
'noise') is produced.2
Noise present, but AM ± FM not operating.3
Any speaker does not work.4
Any AM or FM does not work.5
Few preset turning bands.5
Reception poor.6
Sound quality poor.7
Preset memory disappears.8
Tape PlayerCassette tape cannot be inserted.9
Cassette tape inserted, but no power.10
Power coming in, but tape player not operating.11
Any speaker does not work.12
Sound quality poor.13
Tape jammed, malfunction with tape speed or auto±reverse.14
Cassette tape will not eject.15
CD PlayerCD cannot be inserted.16
CD inserted, but no power.17
Power coming in, but CD player not operating.18
Sound jumps.19
Sound quality poor (Volume faint).20
Any speaker does not work.21
CD will not be ejected.22
Power AmplifierNo power coming in.23
Power coming in, but power amplifier not operating.24
Any speaker does not work.25
NoiseNoise occurs26
Noise produced by vibration or shock while driving.27
Noise produced when engine starts.28
The term ºAMº includes LW,MW and SW, and the term ºFWº includes UKW.
V08418
Turn ignition Key from LOCK position to ACC position.
Troubleshooting for ANTI±THEFT SYSTEM
Display A:
ID Number is set.Display E:
ANTI±THEFT SYSTEM opera-
tion condition. (ID number input
error 10 times or more.)Display B
ºSECº display disappears after 1
second.Radio switch ON.
Take to designated radio
service station.Display BDisplay D
Refer to each
malfunction item.Normal
operation.
Radio switch ON. Normal operation.
Cancel ID number, refer to each malfunction item.
Ye s
No
OK
NG
ANTI±THEFT SYSTEM operation condition. (ID number input error 9 times or less.)
Input ID number to cancel ANTI±THEFT SYSTEM, and check display.
Display A"B Display B Display E
Display C"A
Radio switch ON.Refer to each
malfunction item.Take to designated
radio service station.ANTI±THEFT SYSTEM not can-
celled. (ID number input error 10
times or less.)
Display D
ANTI±THEFT SYSTEM cancelled.
Check audio system again.Normal operation.
OK
NG
Cancel ID number, refer to each malfunction item.
Liquid Crystal Display (LCD) or VFD for Audio System
Display ºAº Display ºBº Display ºCº
Display ºDº Example:Display ºEº
2 DIN Type
1 DIN TypeBlank
No Illumination
2 DIN Type
1 DIN Type 2 DIN Type
1 DIN Type Error Times2 DIN Type 1 DIN Type
Radio Display
1 DIN Type 2 DIN Type
HINT:
Refer to Owner's Manual for operation details of ANTI±THEFT SYSTEM.
When the ID number has been cancelled, reset the same number after completing the operation, or
inform the customer that it has been cancelled.
± BODY ELECTRICALAUDIO SYSTEM
BE±197
2498 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2 RadioDISPLAY INDICATES WHEN POWER SWITCH TURNED TO
ºONº, BUT NO SOUND (INCLUDING ºNOISEº) IS PRODUCED
+ B wire harness faulty.
GND faulty.
Power amplifier faulty.
Speaker wire harness faulty. GND faulty. Is tape player operating normally?
Check if RAD±No.2 fuse is OK?Ye s
NG
No OK No
No
No
No OK
OK
OK Ye s
Ye s
Ye s
Ye sNG
NG
NG Check if RAD±No.1 fuse is OK?
Radio assembly faulty. Recheck system after repair.Replace fuse.
ACC wire harness faulty. Radio assembly faulty.
Replace fuse.
Does continuity exist in speaker wire harness?
Temporarily install another speaker. Functions OK?
Hiss noise from speaker?Ye s
Ye s NoNo
No Ye sPower amplifier faulty.
Power amplifier faulty.
Recheck system after repair. Speaker faulty.
Is power supplied to ACC terminal of power amplifier?
Check if GND (wire harness side) of power amplifier
grounded normally? Is power supplied to +B terminal of power amplifier?
Is power supplied to ACC terminal of radio receiver?
Is power supplied to +B terminal of radio receiver?
Check if GND (wire harness side) of power amplifier
grounded normally?
± BODY ELECTRICALAUDIO SYSTEM
BE±199
2500 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
I04253
Meter Circuit Plate ± 2
Combination Meter ECU
SLIP Indicator
TRAC OFF Indicator
Window Washer Level Warning
ABS Warning
VSC Warning
Brake Fluid Level Warning
ECT SNOW Indicator
Low Oil Pressure Warning
ECT PWR Indicator
Discharge Warning
CRUISE MAIN Indicator
Seat Belt Warning
Rear Light Indicator
Headlight Leveling Indicator
SRS Warning
Open Door Warning
Fog Light IndicatorA/T 2 Indicaor
Engine Oil Level Indicator
Malfunction Indicator
Fuel Level Indicator
Headlight Indicator (USA)
Taillight Indicator (CANADA) ODO/
TRIP
Display
PanelIG+
SLIP
TRC OFF
WASHER
ABS
VSC
BRAKE
ECT SNOW
OIL P
ECT PWR
CHARGE
CRUISE
SEAT BELT
Rr LIGHT
HEAD LVL
AIRBAG
SRS +B
DOOR
FR FOG
COM1
SEG30
TEST1
TEST2
TEST3
GroundCHECK
ENG
IG+
FUEL
IG+
BEAM±
BEAM+ SRS +BTAIL A/T R
A/T L
A/T N
A/T D
OIL LVLDIM+
A/T 2
A/T 3
A/T 4F12
A/T PF11
F10
F9
F8
F5
F4
F2
F1
C7
C5
C3
D12
D8 E11
E10
E9
E8
E7
E6
J1
J33
D6
D4Hi±Beam Indicator
D2 E20
E19
E18
E17
E16
E15
E14
E13
E12
E3
E1 E5
E4A/T 3 Indicaor
A/T 4 Indicaor
A/T P Indicaor
A/T R Indicaor
A/T L Indicaor
A/T N Indicaor
A/T D Indicaor
T1
T2
T3
T4
~~
D10 BE±88
± BODY ELECTRICALCOMBINATION METER
2389 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear)Confirmation
of SymptomsDiagnostic Trouble
Code CheckProblem Condition
Diagnostic Trouble
Code DisplayProblem symptoms
existSame diagnostic
trouble code is
displayedProblem is still occurring in the diagnostic
circuit
Normal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
(The diagnostic trouble code displayed
first is either for a past problem or it is a
secondary problem)
No problem
symptoms existThe problem occurred in the diagnostic
circuit in the past
Normal Code DisplayProblem symptoms
existNormal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
No problem
symptoms existNormal code is
displayedThe problem occurred in a place other
than in the diagnostic circuit in the past
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±23
23 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the LEXUS GS400/GS300 fulfills various functions. The first function is the Diag-
nostic Trouble Code Check in which a malfunction in the signal circuits to the ECU is stored in code in the
ECU memory at the time of occurrence, to be output by the technician during troubleshooting. Another func-
tion is the Input Signal Check which checks if the signals from various switches are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can
be performed effectively. Diagnostic functions are incorporated in the following systems in the LEXUS
GS400/GS300.
SystemDiagnostic Trouble
Code CheckInput Signal Check
(Sensor Check)Diagnostic Test
Mode (Active Test)
Engine (2JZ±GE)
Engine (1UZ±FE)
Automatic Transmission
ABS & Hydraulic Brake Booster Power Supply System
Vehicle Skid Control (VSC) & Brake Assist (BA) System
Power Tilt and Power Telescopic Steering Column
Supplemental Restraint System
Cruise Control System
Engine Immobiliser System
Multiplex Communication System
LEXUS Navigation System
Air Conditioning System(with check Mode)
(with check Mode)
(with check Mode)
In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the current conditions, as shown
in the table below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting
for normally operating systems, thus making it more difficult to locate the problem, or in repairs not pertinent
to the problem. Therefore, always follow the procedure in correct order and perform the diagnostic trouble
code check.