Toyota Sienna Service Manual: 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 between the terminals of the motor.
The voltage difference measured between the terminals of the rear blower motor changes in proportion to the control at the rear blower motor controller on the ground side.
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.
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
2 INSPECT REAR BLOWER MOTOR
(a) Remove the rear blower motor with the connector still connected.
(b) Disconnect the connector from the rear blower motor.
(c) Connect the positive (+) lead to terminal 1 of the rear blower motor connector, and the negative (-) lead to terminal 2.
OK: The rear blower motor operates smoothly.
3 CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR - BATTERY)
(a) Measure the voltage according to the value(s) in the table below.
Standard voltage 
4 CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR CONTROLLER - BODY GROUND)
(a) Disconnect the connector from the rear blower motor controller.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
5 CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR - REAR BLOWER MOTOR CONTROLLER)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
6 CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR CONTROLLER - 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.
7 INSPECT REAR BLOWER MOTOR CONTROLLER
(a) Disconnect the connector from the rear blower motor controller.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
(c) Connect the positive (+) lead to terminal 3 through a 12 V 3.4 W test bulb, and the negative (-) lead to terminal 1.
(d) Connect the three 1.5 V dry cell batteries' positive (+) lead to terminal 2, and the negative (-) lead to terminal 1.
Then check that the test bulb comes on.
OK: The test bulb comes on.
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Rear Air Conditioning Relay Circuit
DESCRIPTION
The RR A/C relay is switched on by signals from the A/C amplifier. It
supplies power to the rear blower
motor.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT RELAY (RR A/C)
...
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 moto ...
Other materials:
Removal
1. PRECAUTION
HINT:
See page RS-1
2. DISCONNECT BATTERY NEGATIVE TERMINAL
Wait for 90 seconds after disconnecting the battery
terminal to prevent the airbag working.
3. PLACE FRONT WHEELS FACING STRAIGHT AHEAD
4. REMOVE STEERING WHEEL COVER LOWER NO.2
(See page RS-424)
5. REMOVE STEERING WH ...
Disassembly
1. REMOVE OIL PUMP RELIEF VALVE
(A) using a 27 mm socket wrench, remove the relief
valve plug.
(B) remove the valve spring and oil pump relief valve.
2. REMOVE OIL PUMP COVER
(a) Remove the 8 bolts, oil pump cover and oil pump
rotor set. ...
If the engine will not
start
If the engine will not start even though correct starting procedures
are being followed (, 228), consider each of the following
points:
The engine will not start even though the starter motor operates
normally.
One of the following may be the cause of the problem:
There may not be sufficien ...
