DESCRIPTION
The radio receiver controls the volume according to the MUTE signal from the television display assembly.
The MUTE signal is sent to reduce noise and a popping sound generated when switching the mode, etc.
If there is an open in the circuit, noise can be heard from the speakers when changing the sound source.
If there is a short in the circuit, even though the radio receiver is normal, no sound or, only an extremely small sound, can be produced.
WIRING DIAGRAM

INSPECTION PROCEDURE
1 INSPECT TELEVISION DISPLAY ASSEMBLY

Standard voltage

2 CHECK HARNESS AND CONNECTOR (RADIO RECEIVER - TELEVISION DISPLAY)

Standard resistance

3 REPLACE TELEVISION DISPLAY ASSEMBLY
OK: The audio system operates normally
REPLACE RADIO RECEIVER
Mute Signal Circuit between Radio Receiver and Stereo Component
Amplifier
AVC-LAN CircuitThrottle Actuator Control System
DESCRIPTION
The throttle actuator is operated by the ECM, and opens and closes the
throttle valve using the gears.
The opening angle of the throttle valve is detected by the Throttle Position
(TP) sensor, which is mounted
on the throttle body. The TP sensor provides feedback to the ECM ...
General information
A large number of ECU controlled systems are used in the
SIENNA. In general, ECU controlled systems are considered
to be very intricate, requiring a high level of technical
knowledge to troubleshoot. However, most problem checking
procedures only involve inspecting the ECU controlled
system's c ...
ABS Warning Light does not Come ON
WIRING DIAGRAM
Refer to ABS Warning Light Remains ON (See page BC-141).
INSPECTION PROCEDURE
1 CHECK ABS WARNING LIGHT
(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Check that the ABS warning light comes on.
OK:
ABS warning light come ...