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:
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 motor, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Start the engine before inspection. Check ...
Inspection
1. INSPECT SEAT HEATER SWITCH LH
Measure the resistance of the seat heater switch
when the switch is operated.
Resistance
If the result is not as specified, replace the switch.
HINT:
As the dial is being turned, the resistance changes
gradually.
Push the seat h ...
Сamshaft timing oil control valve assembly
COMPONENTS
ON-VEHICLE INSPECTION
1. INSPECT CAMSHAFT TIMING CONTROL VALVE ASSEMBLY
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Start the engine and warm it up.
(d) Select the intelligent tester from the ACTIVE TEST
...
