Toyota Sienna Service Manual: AVC-LAN Circuit
DESCRIPTION
Each unit of the audio system connected to the AVC-LAN (communication bus) transfers the signal of each switch by communication.
When a short to +B or short to ground occurs in this AVC-LAN, the audio system will not function normally as the communication is discontinued.
INSPECTION PROCEDURE
1 INSPECT RADIO RECEIVER
- Disconnect the radio receiver connectors.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
*1: 10 Speaker System
2 CHECK HARNESS AND CONNECTOR
HINT: For details of the connectors, refer to the "TERMINALS OF ECU"
- Referring to the AVC-LAN wiring diagram below, check all AVC-LAN circuits.
- Disconnect all connectors in all AVC-LAN circuits.
- Check for an open or short in all AVC-LAN circuits.
OK: There is no open or short circuit
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Mute Signal Circuit between Radio Receiver and Television Display
Assembly
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 ...
Vehicle Speed Signal Circuit between Multi-display and Combination
Meter
DESCRIPTION
This circuit is necessary for the ASL (Auto Sound Leveliser) built into the
radio receiver.
Speed signals are received from the combination meter and used for the ASL.
The ASL fun ...
Other materials:
Poor Sound Quality in All Modes (Low Volume)
INSPECTION PROCEDURE
1 CHECK AUDIO SETTINGS
Set "BASS", "MID", and "TREB" to the initial values and
check that sound is normal.
OK:
Malfunction disappears.
2 COMPARE WITH ANOTHER VEHICLE OF SAME MODEL
Compare with another vehicle of the same model.
...
Mute Signal Circuit between Radio Receiver and Stereo Component
Amplifier
DESCRIPTION
This circuit sends a signal to the stereo component amplifier to mute noise.
Because of that, the noise
produced by changing the sound source ceases.
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 i ...
Inspection
1. INSPECT FRONT STABILIZER LINK ASSEMBLY LH
(a) As shown in the illustration, flip the ball joint stud
back and forth 5 times, before installing the nut.
(b) Using a torque wrench, turn the nut continuously at
a rate of 2 to 4 seconds per 1 turn and take the
torque reading on the 5th tur ...
