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:
Ambient temperature sensor circuit
DTC B1412/12 Ambient Temperature Sensor Circuit
DESCRIPTION
The ambient temperature sensor is installed in front of the condenser to
detect the ambient temperature
which is used to control the air conditioner "AUTO" mode. This sensor is
connected to the A/C amplifier
and detects fl ...
Removal
1. REMOVE REAR WHEEL
2. REMOVE TAIL EXHAUST PIPE ASSEMBLY (See page
EX-8)
3. SEPARATE REAR SPEED SENSOR
(a) Remove the bolt and the speed sensor from the
axle carrier.
NOTICE:
Be careful not to damage the speed sensor
Prevent foreign matter from adhering to the
speed sensor.
4. REMO ...
On-vehicle inspection
HINT:
The type of ignition switch on this model differs according to
the specifications of the vehicle. For the expressions used in
this section, refer to the "EXPRESSIONS OF IGNITION
SWITCH" precaution (See page ES-1).
1. CHECK AIR FUEL RATIO COMPENSATION SYSTEM
(a) Connect the inte ...
