Toyota Sienna Service Manual: Blower Motor Circuit
DESCRIPTION
The blower motor is operated by signals from the A/C amplifier. Blower motor speed signals are transmitted by changes in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For example, if A is the period of continuity in one cycle, and B is the period of non-continuity, then Duty Ratio = A/(A+B) x 100 (%).
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.
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
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 that the blower motor operates.
ACTIVE TEST / AIR CONDITIONER 
OK: The blower motor operates and the blower level changes.
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
3 PERFORM ACTUATOR CHECK
(a) Enter the actuator check mode (See page AC-15).
(b) Press the DEF switch to change to the step operation.
(c) Check the air flow level by hand.
OK: The blower level changes in accordance with each display code.
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
4 INSPECT BLOWER MOTOR
(a) Remove the blower motor.
(b) Disconnect the connector from the blower motor.
(c) Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, and check that the motor operates.
OK: Blower motor operates smoothly.
5 CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BLOWER MOTOR CONTROLLER)
(a) Disconnect the connector from the blower motor.
(b) Disconnect the connector from the blower motor controller.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance 
6 CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BODY GROUND)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
7 CHECK HARNESS AND CONNECTOR (BLOWER MOTOR CONTROLLER - BODY GROUND)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
8 CHECK HARNESS AND CONNECTOR (BLOWER MOTOR CONTROLLER - BATTERY)
(a) Measure the voltage according to the value(s) in the table below.
Standard voltage 
9 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BLOWER MOTOR CONTROLLER)
(a) Disconnect the connector from the A/C amplifier.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
10 INSPECT A/C AMPLIFIER
(a) Reconnect the connector to the A/C amplifier.
(b) Reconnect the connector to the blower motor controller.
(c) Reconnect the connector to the blower motor
(d) Measure the waveform between terminal A9-6 (BLW) of the A/C amplifier and body ground.
OK: Waveform is as shown in the illustration.
HINT:
Waveform varies with the blower level.
REPLACE BLOWER MOTOR CONTROLLER
Multiplex Communication Circuit
DESCRIPTION
INSPECTION PROCEDURE
1 GO TO CAN COMMUNICATION SYSTEM
(a) Refer to the CAN communication system (See page CA-
7).
(b) If the CAN communication system is operating normally,
procee ...
Air Conditioning Compressor Magnetic Clutch Circuit
DESCRIPTION
When the A/C amplifier is turned on, a magnetic clutch ON signal is sent from
the MGC terminal of the A/
C amplifier. Then, the MG CLT relay turns on to operate the magnetic clutch.
W ...
Other materials:
Pressure Control Solenoid "B" Performance (Shift
Solenoid Valve SL2)
SYSTEM DESCRIPTION
The ECM uses signals from the vehicle speed sensor to detect the actual gear
position (1st, 2nd, 3rd, 4th
or 5th gear).
Then the ECM compares the actual gear with the shift schedule in the ECM memory
to detect mechanical
problems of the shift solenoid valves, valve b ...
Problem symptoms table
POWER WINDOW CONTROL SYSTEM (W/ JAM PROTECTION)
Symptom
Suspected Area
AUTO UP/DOWN function does not operate
Power window regulator motor assembly (Driver side)
Wire harness
Power window regulator master switch assembly
Remote ...
Removal
1. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
2. REMOVE REAR NO. 2 SEAT LEG SIDE GARNISH SUB-ASSEMBLY
Disengage the 9 clips and remove the rear No. 2
seat leg side garnish sub-assembly.
Remove the 9 clips from the rear No. 2 seat leg side
garnish sub-assembly.
3. ...
