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:
Adjustment
1. VEHICLE PREPARATION FOR HEADLIGHT AIMING
ADJUSTMENT
Prepare the vehicle:
Ensure there is no damage or deformation to the
body around the headlights.
Fill the fuel tank.
Make sure that the oil is filled to the specified
level.
Make sure that the c ...
Indicator Circuit
DESCRIPTION
This system has two indicator lights. One of the indicator lights is built
into the fold seat switch. This
indicator light receives power from the fold seat control ECU. It comes on or
blinks when the system
detects that an object is caught or when the seat operation conditions ar ...
On-vehicle inspection
1. INSPECT FUEL CUT RPM
(a) Increase the engine speed to at least 3500 rpm.
(b) Use a sound scope to check for injector operating
sounds.
(c) Check that when the throttle lever is released,
injector operating sounds stop momentarily (at 2500
rpm) and then resume (at 1400 rpm).
Standard
...
