Toyota Sienna Service Manual: Poor Sound Quality in All Modes (Low Volume)
INSPECTION PROCEDURE
1 CHECK AUDIO SETTINGS
- Set "BASS", "MID" and "TREB" to the initial values and check that sound is normal.
OK: Malfunction disappears.
2 COMPARE WITH ANOTHER VEHICLE OF SAME MODEL
- Compare with another vehicle of the same model.
- Compare with another vehicle of the same model which does not have trouble to see if there is any difference in the sound quality.
OK: No difference is found
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Screen Flicker or Color Distortion
INSPECTION PROCEDURE
1 CHECK DISPLAY SETTING
Enter the display adjustment screen by pressing the
"DISPLAY" switch.
Reset display settings (contrast, brightness) and check
...
Map Disc cannot be Inserted
INSPECTION PROCEDURE
1 CHECK RADIO AND NAVIGATION ASSEMBLY
Check if a disc is inserted into the MAP disc slot.
Check if "DISC IN" is displayed.
OK:
"DISC IN&quo ...
Other materials:
On-vehicle inspection
1. CHECK POWER SEAT FUNCTION
Check the basic functions.
Operate the power seat switches and check the
following seat functions:
Sliding
Reclining
Front vertical (Driver side seat only)
Lifter (Driver side seat only)
Lumbar suppo ...
Radio Receiver Power Source Circuit
DESCRIPTION
This circuit provides power to the radio receiver.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT RADIO RECEIVER ASSEMBLY
Disconnect the radio receiver connector.
Measure the resistance according to the value in the
table below.
Standard resistance
Measure t ...
Engine immobilizer
system
The vehicle’s keys have built-in transponder chips that prevent
the engine from starting if a key has not been previously registered
in the vehicle’s on-board computer.
Never leave the keys inside the vehicle when you leave the vehicle.
This system is designed to help prevent vehicle the ...
