Toyota Sienna Service Manual: System description
1. MULTIPLEX COMMUNICATION SYSTEM (BEAN)
- The BEAN communication line is used to control the
combination meter, the A/C amplifier, the airbag
sensor assembly, the multiplex network body ECU,
the power slide door ECU LH, the power slide door
ECU RH, the power back door ECU, the seat
position control ECU, the outer mirror control ECU
LH, and the outer mirror ECU RH. If there is a shortcircuit
(bus-down) in the line, the communication to
the system that has a short-circuit (bus-down) will
be disabled and the DTC concerning the system will
be output from the multiplex network gateway ECU.


- If the DTC of ECU communication stop is output,
connectors may be disconnected, or communication
buses may be open at 2 points. It will not become
abnormal with only 1 communication bus open.

- If 2 communication buses are open at the points
shown in the illustration, the DTC of ECU
communication stop between those 2 buses is
output.
2. CHECK COMMUNICATION FUNCTION
- Check the battery voltage.
Standard voltage:
11 to 14 V
- Inspect the DTC output.
- Check a DTC concerning the multiplex network
body ECU by connecting the intelligent tester to
the DLC3 and turning the ignition switch to the
ON position.
- When the display shows DTCs concerning the
ECU unconnected and the communication bus
defective, perform the inspection depending on
the troubleshooting procedures.
HINT:
When another DTC is output, refer to the DTC
table and check the applicable section.
HINT:
Troubleshoot in accordance with the procedures on the
following pages.
1 VEHICLE BROUGHT TO WORKSHOP
2 DTC CHECK
Check for DTCs and make a note of the code that is
output (See page MP- ...
Other materials:
Inspection
1. INSPECT BRAKE VACUUM CHECK VALVE ASSEMBLY
(a) Check the vacuum check valve.
(1) Slide the clip and disconnect the vacuum hose.
(2) Remove the vacuum check valve.
(3) Check that there is ventilation from the booster
to the engine, and no ventilation from the
engine to the booster.
...
Installation
1. INSTALL TRANSFER CASE OIL SEAL
(a) Using SST, install anew transfer case oil seal to the
transfer case at the position shown in the
illustration.
SST 09387-00010, 09950-70010 (09951-07150)
NOTICE:
Do not install it obliquely.
(b) Apply small amount of MP grease to the oil seal lip.
2. ...
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 ...