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:
Removal
1. DISCONNECT BATTERY NEGATIVE TERMINAL
2. REMOVE FRONT DOOR SCUFF PLATE LH
3. REMOVE COWL SIDE TRIM BOARD LH
4. REMOVE INSTRUMENT PANEL FINISH PANEL SUBASSEMBLY
LOWER LH (See page IP-6)
5. REMOVE REAR DOOR SCUFF PLATE RH
6. REMOVE REAR DOOR SCUFF PLATE LH
7. REMOVE FRONT SEAT ASSEMBLY LH
HI ...
Disc cannot be Played/ No Playable Files/ Copyright Protection Error
DTC 44-7D Disc cannot be Played
DTC 44-7E No Playable Files
DTC 44-7F Copyright Protection Error
DESCRIPTION
DTC No.
DTC Detecting Condition
Trouble Area
44-7D
An incompatible MP3/WMA file is used.
Although the file has an extension of ".mp3 ...
Lock Switch Circuit
DESCRIPTION
Each of the left and right seats has lock switches that detect the lock
condition of the seat legs to the floor
when the seat is in the original or folded-down state. If any of the lock
switches detect an unlock condition,
the 3rd SEAT indicator on the combination meter will come ...
