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:
Rear Occupant Classification Sensor RH Collision
Detection
DTC B1788 Rear Occupant Classification Sensor RH Collision
Detection
DESCRIPTION
DTC B1788 is output when the occupant classification ECU receives a collision
detection signal sent by
the rear occupant classification sensor RH if an accident occurs.
DTC B1788 is also output when the front s ...
Light Control Switch Circuit
DESCRIPTION
This circuit detects the state of the headlight dimmer switch.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
Connect the intelligent tester to DLC3.
Turn the ignition switch ON and push the intelligent
tester main switch ON.
Select t ...
Short in CAN Bus Lines
DESCRIPTION
The CAN bus wires are considered to be shorted when the resistance between
terminals 6 (CANH) and
14 (CANL) of the DLC3 is below 54 Ω.
Symptom
Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3
is below 54 Ω.
...
