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:
Cranking Holding Function Circuit
DESCRIPTION
The system detects the ignition switch's starting signal (STSW) and then
supplies current to the starter
until the ECM judges that the engine has started successfully. The purpose is to
reduce the holding time
of the ignition key.
WIRING DIAGRAM
Refer to DTC P0617 (See page ...
ECU Power Source Circuit
DESCRIPTION
This circuit provides power to operate the theft deterrent (warning) ECU.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
Remove the ECU-B fuse from the engine room J/B.
Measure the resistance.
Standard resistance:
Below 1 Ω
2 CHECK INSTRUMENT PANEL ...
Radio Broadcast cannot be Received or Poor Reception
INSPECTION PROCEDURE
1 CHECK RADIO RECEIVER
Check the radio's automatic station search function.
Check the radio's automatic station search function
by activating it.
OK:
The radio's automatic station search function
works properly.
2 CONFIRM MODEL
Result
3 INSPECT RADIO ...
