2003 LEXUS LS430 Diagram ac amplifier

Fig. 72: Identifying Blinking Pattern
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: GO TO COMBINATION METER SYSTEM (SEE PRECAUTION
)
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS
TABLE
CIRCUIT DESCRIPTION
This circuit sends the signal to the stereo component amplifier to mute the noise. Because of that, the noise
produced by changing the sound source ceases.
In addition, this circuit is used to mute the sound when the navigation system performs voice guide.
If there is an open in the circuit, noise can be heard from the speaker when changing the sound source.
When the vehicle is equipped with the navigation system, audio sound keeps coming out from the speaker on
the driver's side while the voice navigation is in operation.
If there is a short in the circuit, even though the stereo component amplifier assy is normal, no sound or only
extremely small sound can be produced.
WIRING DIAGRAM

Fig. 73: Stereo Component Amplifier Assy Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT STEREO COMPONENT AMPLIFIER ASSY
a. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
MUTE - Body
groundTurn ignition switch to ACC. Audio system is playing -->
ChangingAbove 3.5 V --> Below
1 V

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

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. 88: Identifying Stereo Component Amplifier Assy
- Audio And Rear A/C Control SW Wiring
Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSY - AUDIO
AND REAR A/C CONTROL SW)
a. Disconnect the connector from the stereo component amplifier assy S29 and audio and rear A/C
control SW A35.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION CONDITION CHART
Tester connectionConditionSpecified condition
TX+ - TXD+(1), RTX+(2)AlwaysBelow 1 ohms
TX- - TXD-(1), RTX-(2)AlwaysBelow 1 ohms
TX+ - Body groundAlways10 kohms or higher
TX- - Body groundAlways10 kohms or higher
(1)Mark Levinson Models
(2)Standard Models

Fig. 22: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE CLEARANCE WARNING ECU ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Ultrasonic sensor consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the
clearance warning ECU assy.
Fig. 23: DTC B2232 Detection Condition And Trouble Area Description Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM

Fig. 26: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE CLEARANCE WARNING ECU ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Ultrasonic sensor consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the
clearance warning ECU assy.
Fig. 27: DTC B2233 Detection Condition And Trouble Area Description Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM

Fig. 30: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE CLEARANCE WARNING ECU ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Ultrasonic sensor consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the
clearance warning ECU assy.
Fig. 31: DTC B2234 Detection Condition And Trouble Area Description Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM

Fig. 34: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE CLEARANCE WARNING ECU ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Ultrasonic sensor consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the
clearance warning ECU assy.
Fig. 35: DTC B2235 Detection Condition And Trouble Area Description Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM