Toyota Sienna Service Manual: Rear Room Temperature Sensor Circuit
DESCRIPTION
This sensor detects the rear cabin temperature that is used as the basis for
temperature control and
sends a signal to 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 item 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 REAR A/C ROOM TEMPERATURE SENSOR
(a) Remove the rear A/C room temperature sensor.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
NOTICE:
- Hold the sensor only by its connector. Touching the sensor may change the resistance value.
- When measuring, the sensor temperature must be the same as the rear cabin temperature.
HINT: As the temperature increases, the resistance decreases (see the graph).
3 CHECK HARNESS AND CONNECTOR (REAR A/C ROOM TEMPERATURE SENSOR - A/C AMPLIFIER)
(a) Disconnect the connector from the A/C amplifier.
(b) Disconnect the connector from the rear A/C room temperature sensor.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance 
REPLACE A/C AMPLIFIER
Rear evaporator temperature sensor circuit
DESCRIPTION
The rear evaporator temperature sensor is installed on the rear evaporator.
It detects the rear evaporator
temperature. The sensor sends a signal to the A/C amplifier. The resistance o ...
Solar Sensor Circuit (Passenger Side)
DTC B1421/21 Solar Sensor Circuit (Passenger Side)
DESCRIPTION
The solar sensor, which is installed on the upper side of the instrument
panel, detects sunlight and
controls the air conditioni ...
Other materials:
Inspection
1. INSPECT TIRE PRESSURE WARNING RESET SWITCH
(a) Remove the tire pressure warning reset switch.
(b) Measure the resistance between terminals 1 and 2
of the tire pressure warning reset switch when the
tire pressure warning switch is ON and OFF.
Standard resistance
If the result is not as ...
Automatic transaxle unit
COMPONENTS
...
Starting the engine
Check that the parking brake is set.
Check that the shift lever is set in P.
Firmly depress the brake pedal.
The engine switch indicator will turn green. If the indicator does not turn
green, the engine cannot be started.
Press the engine switch.
The engine will crank until it sta ...