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:
For front passenger side
ON-VEHICLE INSPECTION
1. INSPECT AIR MIX CONTROL SERVO MOTOR
(a) Remove the air mix control servo motor.
(b) Connect the positive (+) lead from the battery to
terminal 4 and negative (-) lead to terminal 5, then
check that the lever turns to "COOL" side smoothly.
(c) Connect ...
System description
1. DESCRIPTION OF OCCUPANT CLASSIFICATION SYSTEM
GENERAL DESCRIPTION.
In the occupant classification system, the
occupant classification ECU calculates the
weight of the occupant based on a signal from
the occupant classification sensors. This system
recognizes the occu ...
Open in One Side of CAN Branch Line
DESCRIPTION
If 2 or more ECUs and/or sensors do not appear on the intelligent tester
"Communication Bus Check"
screen, one side of the CAN branch wire may be open. (One side of the CAN-H
[branch wire] / CAN-L
[branch wire] of the ECU and/or sensor is open.)
Symptom
...
