Toyota Sienna Service Manual: Air Inlet Damper Position Sensor Circuit
DESCRIPTION
This sensor detects the position of the air inlet control servo motor and sends the appropriate signals to the A/C amplifier. The position sensor is built in the air inlet control servo motor.
The position sensor's resistance changes as the air inlet control servo motor arm moves.
It outputs voltage (5 V) that is input to terminal 1 and terminal 3 via the variable resistor, and then to the A/ C amplifier.
The A/C amplifier determines the arm position based on the input voltage from
the position sensor. 
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 below in the DATA LIST, and read the display on the intelligent tester.
DATA LIST / AIR CONDITIONER 
OK: The display is as specified in the normal condition column.
Result 
2 INSPECT AIR INLET CONTROL SERVO MOTOR
(a) Remove the air inlet control servo motor.
(b) Disconnect the connector from the air inlet control servo motor.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance 
(d) Measure the resistance according to the value(s) in the table below.
Standard resistance 
(e) As the air inlet control servo motor moves from RECIRCULATION to FRESH, the resistance decreases gradually without interruption.
3 CHECK HARNESS AND CONNECTOR (AIR INLET 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
Standard resistance
Air Mix Damper Position Sensor Circuit (Passenger Side)
DESCRIPTION
This sensor detects the position of the air mix control servo motor (air mix
damper) and sends the
appropriate signals to the A/C amplifier. The position sensor is built in the
a ...
Air Outlet Damper Position Sensor Circuit
DESCRIPTION
This sensor detects the position of the air outlet control servo motor and
sends the appropriate signals to
the A/C amplifier. The position sensor is built in the air outlet contro ...
Other materials:
On-vehicle inspection
1. INSPECT DRIVE BELT
(a) Visually check the drive belt for excessive wear,
frayed cords, etc.
If any defect is found, replace the drive belt.
HINT:
Cracks on the rib side of a belt are considered
acceptable. Replace the belt if there are any
missing ribs.
2. CHECK POWER STEERING FLUID ...
Evaporator temperature sensor circuit
DESCRIPTION
The evaporator temperature sensor (A/C thermistor) is installed on the
evaporator in the air conditioning
unit. It detects the temperature of the cooled air that has passed through the
evaporator and its signal is
used to control the air conditioning. It sends a signal to the A/C ...
Removal
1. REMOVE FRONT EXHAUST PIPE ASSEMBLY
HINT:
(See page EX-8)
2. REMOVE PROPELLER WITH CENTER BEARING
SHAFT ASSEMBLY
HINT:
(See page PR-3)
3. REMOVE REAR DIFFERENTIAL FILLER PLUG
(a) Using a hexagon wrench (10 mm), remove the filler
plug and gasket.
4. REMOVE REAR DIFFERENTIAL DRAIN PLUG
(a ...
