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:
Inspection
1. Inspect heated oxygen sensor (for bank 1
sensor 2)
(a) Measure the resistance of the sensor.
Standard resistance
If the resistance is not as specified, replace the
sensor.
2. HEATED OXYGEN SENSOR (for Bank 2 Sensor 2)
(a) Measure the resistance of the sensor.
Standard resistance ...
Compressor Lock Sensor Circuit
DTC B1422/22 Compressor Lock Sensor Circuit
SYSTEM DESCRIPTION
The ECM sends an engine speed signal to the A/C amplifier via CAN
communication and BEAN
communication.
The A/C amplifier reads the difference between compressor speed and engine
speed. When the
difference becomes too large, t ...
ABS Warning Light does not Come ON
WIRING DIAGRAM
Refer to ABS Warning Light Remains ON (See page BC-141).
INSPECTION PROCEDURE
1 CHECK ABS WARNING LIGHT
(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Check that the ABS warning light comes on.
OK:
ABS warning light come ...
