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:
Removal
1. PRECAUTION
CAUTION: Be sure to read "PRECAUTION" thoroughly before
servicing.
2. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
CAUTION:
Wait for 90 seconds after disconnecting the cable to
prevent the airbag working.
3. PLACE FRONT WHEELS FACING STRAIGHT AHEAD
4. REMOVE STEE ...
For vehicles equipped with catalytic converter
CAUTION: If a large amount of unburned gasoline or gasoline vapors flow
into the converter, it may cause overheating and create a fire hazard. To
prevent this, observe the following precautions:
(a) Use only unleaded gasoline.
(b) Avoid idling the engine for more than 20 minutes.
(c) ...
Basic inspection
(a) WHEN MEASURING RESISTANCE OF
ELECTRONIC PARTS
(1) Unless otherwise stated, all resistance
measurements should be made at an ambient
temperature of 20°C (68°F). Resistance
measurements may be inaccurate if measured
at high temperatures, i.e. immediately after the
vehicle has been running ...
