2003 LEXUS LS430 Identifying condition

Fig. 50: Identifying Audio And Rear A/C Control SW Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT AUDIO AND REAR A/C CONTROL SWITCH (+B, ACC, GND)
a. Disconnect the audio and rear A/C control switch connector A35.
b. Measure the resistance according to the value (s) in the table below.
TESTER CONNECTION CONDITION CHART
c. Measure the voltage according to the value (s) in the table below.
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
GND - Body groundAlwaysBelow 1 ohms
Tester connectionConditionSpecified condition
+B - GNDAlways10 to 14V

Fig. 60: Identifying Radio Receiver Assy - Amp Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSY - STEREO COMPONENT
AMPLIFIER ASSY)
a. Disconnect the connectors from the radio receiver assy R2 and stereo component amplifier assy
S29.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionSpecified condition
L+ (R2) - L+ (S29)Below 1 ohms
L- (R2) - L- (S29)Below 1 ohms
R+ (R2) - R+ (S29)Below 1 ohms
R- (R2) - R- (S29)Below 1 ohms
L+ (R2 or S29) - Body ground10 kohms or higher
L- (R2 or S29) - Body ground10 kohms or higher
R+ (R2 or S29) - Body ground10 kohms or higher
R- (R2 or S29) - Body ground10 kohms or higher

Fig. 64: Identifying Radio Receiver Assy - Stereo Component Tuner Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSY - STEREO COMPONENT
TUNER)
a. Disconnect the connectors from the radio receiver assy R3 and stereo component tuner S31.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionSpecified condition
RR+ - FR+Below 1 ohms
RR- - FR-Below 1 ohms
RL+ - FL+Below 1 ohms
RL- - FL-Below 1 ohms
RR+ - Body ground10 kohms or higher
RR- - Body ground10 kohms or higher
RL+ - Body ground10 kohms or higher
RL- - Body ground10 kohms or higher

WIRING DIAGRAM
Fig. 67: Identifying Stereo Component Amplifier Assy Wiring Diagram

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSY -
COMBINATION METER ASSY)
a. Disconnect the connectors from the stereo component amplifier assy S29 and combination meter
assy C12.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
SPD - +SAlwaysBelow 1 ohms
SPD - Body groundAlways10 kohms or higher

Fig. 75: Identifying Stereo Component Amplifier Assy
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: Go to step 2
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS
TABLE
2.CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSY - STEREO COMPONENT
AMPLIFIER ASSY)
a. Disconnect the connectors from the radio receiver assy R2 and stereo component amplifier assy
S29.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
MUTE (R2) - MUTE (S29)AlwaysBelow 1 ohms
MUTE (R2 or S29) - Body groundAlways10 kohms or higher

WIRING DIAGRAM
Fig. 79: Identifying Radio Receiver Assy
- Stereo Component Tuner Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT STEREO COMPONENT TUNER
a. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
NG: Go to step 2
Tester connectionConditionSpecified condition
MUTE - Body
groundTurn ignition switch to ACC. Audio system is playing -->
ChangingAbove 3.5 V --> Below
1 V

Fig. 83: Identifying Steering Pad Switch Item Condition Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
NG: REPLACE STEERING PAD SWITCH (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Each unit of the radio receiver system connected to AVC-LAN (communication bus) communicates by
transferring the signals from each switch.
When +B short and GND short occur in this AVC-LAN, radio receiver system will not function normally as
communication is discontinued.
In AVC-LAN, radio receiver assy becomes the communication master, and the radio receiver assy has enough
resistance necessary for transmitting the communication.
WIRING DIAGRAM

Fig. 84: Identifying Stereo Component Amplifier Assy - Stereo Component Tuner Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSY -
STEREO COMPONENT TUNER)
a. Disconnect the connector from the stereo component amplifier assy S29 and stereo component
tuner S31.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
TX+(1), MTX+(2) - ATX+AlwaysBelow 1 ohms
TX-(1), MTX-(2) - ATX-AlwaysBelow 1 ohms
MTX+ - Body groundAlways10 kohms or higher