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:
Rear Room Temperature Sensor Circuit
DESCRIPTION
This sensor detects the rear cabin temperature that is used as the basis for
temperature control and
sends a signal to the A/C amplifier.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ign ...
Terminals of ECU
1. TELEVISION CAMERA ASSEMBLY
Disconnect the T10 camera connector
Measure the voltage and resistance of each
terminal of the wire harness side connector.
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the T10 ...
Freeze frame data
1. DESCRIPTION
(a) The ECM records vehicle and driving condition
information as freeze frame data the moment a DTC
is stored. When troubleshooting, freeze frame data
can be helpful in determining whether the vehicle
was running or stopped, whether the engine was
warmed up or not, whether the a ...
