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:
AVC-LAN Circuit
DESCRIPTION
Each unit of the navigation 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 navigation
system will not function
normally as the communication is discontin ...
Basic inspection
When a malfunction is not confirmed by the DTC check,
troubleshooting should be carried out in all circuits
considered to be possible causes of the problem. In many
cases, by carrying out the basic engine check shown in the
following flowchart, the location of the problem can be found
quickly a ...
Data list / active test
1. READ DATA LIST
HINT:
Using the intelligent tester's DATA LIST allows switch,
actuator and other item values to be read without
removing any parts. Reading the DATA LIST early in
troubleshooting is one way to save time.
Connect the intelligent tester with CAN VIM to the
DLC3.
&n ...
