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:
Disassembly
1. REMOVE FRONT DISC BRAKE BUSH DUST BOOT
(a) Using soft jaws on the vise, hold the front disc brake
cylinder mounting LH in the vise through aluminum
plates.
(b) Using a screwdriver and hammer, remove the 2
front disc brake bush dust boots from the front disc
brake cylinder mounting LH. ...
How to proceed with
troubleshooting
HINT:
Troubleshoot in accordance with the procedures on the
following pages
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK
3 INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX
COMMUNICATION SYSTEM (BEAN)
Use the intelligent tester to check for normal ...
How to proceed with
troubleshooting
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS
Interview the customer and confirm the trouble.
Confirm the problem by duplicating the conditions
described by the customer
3 BASIC INSPECTION
Basic inspection.
Measure the battery voltage.
Standard voltage:
11 ...
