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:
Fail-safe chart
1. FAIL-SAFE
This function minimizes the loss of the ECT functions
when any malfunction occurs in a sensor or solenoid.
(a) ATF (Automatic Transmission Fluid) temperature
sensor:
When the ATF temperature sensor has a
malfunction, 5th upshift is prohibited.
(b) Counter gear speed sensor NC ...
Occupant Classification ECU Malfunction
DTC B1795 Occupant Classification ECU Malfunction
DESCRIPTION
DTC B1795 is recorded when a malfunction is detected in the occupant
classification ECU.
Troubleshoot DTC B1771 first when the DTCs B1771 and B1795 are output
simultaneously.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK DTC ...
Initialization
HINT:
The seatback position is initialized at the factory before
shipment, so initialization is not normally required.
There is an initialization function for cases when
reinitialization is required.
Before performing initialization procedure and initialization
release step ...