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:
Diagnosis system
1. CHECK DLC3
The vehicle's ECU uses ISO 15765-4 for
communication protocol. The terminal arrangement
of the DLC3 complies with SAE J1962 and matches
the ISO 15765-4 format.
NOTICE:
*: Before measuring the resistance, leave the
vehicle as is for at least 1 minute and do not
...
Voice Guidance does not Function
INSPECTION PROCEDURE
1 CHECK NAVIGATION SYSTEM SETTING
Enter the "Menu" screen by pressing the "MENU" switch.
Select "Volume".
Check that "OFF" is not selected.
OK:
"OFF" is not selected
2 CHECK NAVIGATION SETTING
...
Terminals of ECU
1. CHECK POWER SLIDE DOOR ECU LH (WITH
POWER SLIDE DOOR)
Disconnect the P25 and P26 ECU connectors, and
check the voltage and resistance of each terminal of
the wire harness side connectors.
If the result is not as specified, there may be a
malfunction on the wire harness side.
...
