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:
How to proceed with
troubleshooting
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-14).
Delete the DTC.
Check if the DTC is output once again when the problem
symptom is simulat ...
What to do if... (Troubleshooting)
If there is a problem with the hands-free system or a Bluetooth®
device, first check the table below.
When using the hands-free system with a Bluetooth® device
The hands-free system or Bluetooth® device does not
work.
The connected device may not be a compatible Bl ...
Driving assist systems
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving
situations. Be aware, however, that these systems are supplementary
and should not be relied upon too heavily when operating
the vehicle.
ABS (Anti-lock Brake System)
Help ...
