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:
Removal
1. REMOVE FRONT SEAT INNER BELT ASSEMBLY
HINT:
Refer to the instructions for disassembly of the front
seat assembly (for flat type).
Refer to the instructions for disassembly of the front
seat assembly (for manual seat).
Refer to the instructions for disassembly of the ...
Customize parameters
HINT:
The following items can be customized.
NOTICE:
When the customer requests a change in a function,
first make sure that customization of the function(s) is
possible.
Be sure to record the current settings before
customizing.
When troubleshooting a function, fir ...
Removal
1. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
2. REMOVE HEATED OXYGEN SENSOR (for Bank 1
Sensor 2)
(a) Disconnect the sensor connector under the center
console.
(b) Using SST, remove the heated oxygen sensor.
SST 09224-00010
3. REMOVE FRONT EXHAUST PIPE ASSEMBLY
(a) Disconnect ...
