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. CONNECT INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine and run at idle.
(c) Select the ACTIVE TEST mode on the intelligent
tester.
HINT:
Please refer to the intelligent tester operator's
manual for further details.
2. INSPECT ACTUATOR MOTOR ...
Meter Illumination is Always Dark
DESCRIPTION
Confirm that the vehicle is equipped with the optitron meter, then
check this circuit.
The combination meter assembly receives a auto dimmer signal from the
body ECU by the multiplex
communication line.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK MULTIPLEX CO ...
Air outlet control servo motor
ON-VEHICLE INSPECTION
1. INSPECT AIR OUTLET CONTROL SERVO MOTOR
(a) Remove the air outlet control servo motor.
(b) Connect the positive (+) lead from the battery to
terminal 4 and negative (-) lead to terminal 5, then
check that the lever turns to "DEF" position.
(c) Connect ...
