Toyota Sienna Service Manual: No. 1 Clearance Warning Buzzer Circuit
DESCRIPTION
The clearance warning ECU receives the ultrasonic sensor signal to sound the front warning buzzer.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FRONT BUZZER
- Remove the clearance warning ECU with front buzzer.
- Apply the battery voltage to the terminals 1 and 2 of the buzzer, and check that the buzzer sounds.
HINT: The clearance warning buzzer is separately excited, and will not sound unless an alternating voltage is applied.
OK: Operating noise (clicking sounds) can be heard.
2 CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - FRONT BUZZER)
- Disconnect the clearance warning ECU connector and front buzzer connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Rear Clearance Sonar Sensor RH Circuit
DESCRIPTION
An ultrasonic sensor consists of a sensor portion that transmits and receives
ultrasonic waves and a preamplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic wave ...
Clearance Warning ECU Power Source Circuit
DESCRIPTION
This circuit provides power to the clearance warning ECU.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - AIR CONDITIONER
AMPLIFIER)
...
Other materials:
Installation
1. INSTALL DISTANCE CONTROL ECU ASSEMBLY
Using a torque wrench, install the bolt.
Torque: 5 N*m (51 kgf*cm, 44 in.*lbf)
NOTICE:
Do not install the dropped or shocked distance
control ECU assembly.
2. INITIALIZE DISTANCE CONTROL ECU
NOTICE:
After replacing the distance control ECU ...
Freeze frame data
1. FREEZE FRAME DATA
(a) Whenever a DTC is detected or the ABS operates,
the skid control ECU stores the current vehicle
(sensor) state as freeze frame data.
The skid control ECU stores the number of times
(maximum: 31) the ignition switch has been turned
from OFF to the ON position since th ...
Reassembly
1. APPLY HIGH TEMPERATURE GREASE
(a) Apply the high temperature grease to the surface on
which the shoe and backing plate attach.
2. INSTALL PARKING BRAKE SHOE LEVER LH
(a) Install the shoe lever and shim to the rear shoe with
a new C-washer.
(b) Using a feeler gauge, measure the clearance.
...
