Toyota Sienna Service Manual: Rear Air Mix Damper Control Servo Motor Circuit
DESCRIPTION
The rear air mix control servo motor (water valve servo motor) is controlled by the A/C amplifier.
The rear air mix control servo motor moves the air mix damper by rotating
(normal, reverse) with electrical
power from the A/C amplifier.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
(c) Select the items in the DATA LIST, and read the display on the intelligent tester.
DATA LIST / AIR CONDITIONER 
OK: When the target position is "MAX. COOL" (0%), the actual opening angle is 19.0% or less.
When the target position is "MAX. HOT" (86.5%), the actual opening angle is 81.0% or more.
Result 
2 PERFORM ACTIVE TEST BY INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
(c) Select the item below in the ACTIVE TEST and then check the air flow temperature by hand.
ACTIVE TEST / AIR CONDITIONER 
OK: When the lever is moved to the "MAX. HOT" side, warm air comes out.
When the lever is moved to the "MAX. COOL" side, cool air comes out.
Result 
3 PERFORM ACTUATOR CHECK
(a) Enter the actuator check mode (See page AC-15).
(b) Press the DEF switch and change to the step operation.
(c) Check the air flow temperature by hand.
OK: Air flow temperature changes in accordance with each display code.
Result 
4 INSPECT REAR AIR MIX CONTROL SERVO MOTOR (WATER VALVE SERVO MOTOR)
(a) Remove the rear air mix control servo motor (water valve servo motor).
(b) Disconnect the connector from the rear air mix control servo motor.
(c) Connect the positive (+) lead from the battery to terminal 5 and the negative (-) lead to terminal 4, then check that the lever turns to the "MAX. COOL" position smoothly.
OK: Lever turns to "MAX. COOL" position smoothly.
(d) Connect the positive (+) lead from the battery to terminal 4 and the negative (-) lead to terminal 5, then check that the lever turns to the "MAX. HOT" position smoothly.
OK: Lever turns to "MAX. HOT" position smoothly.
5 CHECK HARNESS AND CONNECTOR (REAR AIR MIX CONTROL SERVO MOTOR - A/C AMPLIFIER)
(a) Disconnect the connector from the A/C amplifier.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
REPLACE A/C AMPLIFIER
Air Mix Damper Control Servo Motor Circuit (Driver Side)
DESCRIPTION
The air mix control servo motor (air mix damper servo sub-assembly) is
controlled by the A/C amplifier.
The air mix control servo motor moves the air mix damper by rotating (normal, ...
Rear Air Outlet Damper Control Servo Motor Circuit
DESCRIPTION
This circuit turns the servo motor and changes each damper position by
receiving the signals from the A/
C amplifier.
The rear air outlet damper servo motor switches the air outlet ...
Other materials:
Terminals of ECU
1. CHECK POWER SLIDE DOOR ECU LH
Disconnect the P25 and P26 ECU connectors, and
check the voltage and resistance of each terminal of
the wire harness side connectors
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the EC ...
Illumination Circuit
DESCRIPTION
The Multiplex network body ECU controls illumination light as shown in the
chart below.
Room light assembly (Interior light, luggage component light) and
courtesy light with DOOR position
Map light assembly (Personal light)
Transponder key amplifier (Ignition ke ...
Problem symptoms table
Use the table below to find the cause of the problem. The
numbers indicate the priority of the likely cause of the
problem. Check each part in order. If necessary, replace
these parts.
Front A/C:
Rear A/C:
...
