Toyota Sienna Service Manual: IG Power Source Circuit
DESCRIPTION
The main power source is supplied to the A/C amplifier when the ignition switch is turned to the ON position.
The power source is used for operating the A/C amplifier and servo motor, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT: Start the engine before inspection. Check the IG1 relay or battery if the engine does not start.
1 INSPECT FUSE (HTR)
(a) Remove the HTR fuse from the driver side junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
2 INSPECT A/C AMPLIFIER (IG - GND)
(a) Remove the A/C amplifier with its connectors still connected.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage 
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
3 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
4 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BODY GROUND)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
REPLACE A/C AMPLIFIER
Rear Blower Motor Circuit
DESCRIPTION
Power to the rear blower motor is supplied from the battery via the RR A/C
relay.
The rear blower motor speed level varies between 0 and 31 based on the voltage
difference measured ...
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:
Memory recall function
Each electronic key can be registered to recall your preferred driving
position.
Registering procedure
Record your driving position to button “1” or “2” before performing
the following:
Carry only the key you want to register, and then close the driver’s
door.
If 2 or more keys ar ...
DVD Error/ Excess Current/ Tray Insertion / Ejection Error
DTC 44-44 DVD Error
DTC 44-48 Excess Current
DTC 44-50 Tray Insertion / Ejection Error
DESCRIPTION
DTC No.
DTC Detection Condition
Trouble Area
44-44
Operation error in the DVD mechanism
Television display assembly
44-48
Excess current is prese ...
Open in Side Squib RH Circuit
DTC B0111/44 Open in Side Squib RH Circuit
DESCRIPTION
The side squib RH circuit consists of the center airbag sensor assembly and
the front seat side airbag
assembly RH.
The circuit instructs the SRS to deploy when deployment conditions are met.
DTC B0111/44 is recorded when an open circ ...
