Toyota Sienna Service Manual: Back-up Power Source Circuit
DESCRIPTION
This is the back-up power source for the A/C amplifier. Power is supplied even when the ignition switch is off and is used for diagnostic trouble code memory, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
(a) Remove the ECU-B fuse from the engine room junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
2 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)
(a) Disconnect the connector from the A/C amplifier.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
ACC Power Source Circuit
DESCRIPTION
This circuit supplies power to the A/C amplifier and the illumination for the
clock.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU ACC)
(a) Remove the ECU ACC fuse fr ...
Other materials:
Description of initialization
(a) Perform initialization in the following cases:
Before delivery of a new vehicle.
After replacement of the tire pressure warning
ECU*.
After replacement of the tire pressure warning
valve and transmitter.
Specified tire pressure changes depending on
the size or type of the tire.
...
Removal
HINT:
Use the same procedures for the RH side and LH side.
The procedures listed below are for the LH side.
1. PRECAUTION
CAUTION:
Be sure to read "PRECAUTION" thoroughly before
servicing.
2. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
CAUTION:
Wait for 90 s ...
Disassembly
1. REMOVE OCCUPANT CLASSIFICATION ECU
2. REMOVE FRONT SEAT CUSHION SHIELD INNER RH
Remove the screw.
Using a screwdriver, disengage the claws and
remove the cushion shield inner.
HINT:
Tape the screwdriver tip before use.
3. REMOVE FRONT SEAT INNER BELT ASSEMBLY RH
&nbs ...
