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:
Problem symptoms table
Before inspecting the suspected areas listed in the table
below, check the fuse and relay.
Before inspecting the suspected areas listed in the table
below, check the DTCs.
Methods used to verify the cause of the problem are listed
in order of probability in the suspected are ...
Headlight leveling switch
ON-VEHICLE INSPECTION
1. HEADLIGHT LEVELING SWITCH
Connect the battery positive (+) lead to the terminal
1 and the battery negative (-) lead to the terminal 5.
Measure the resistance between the terminal 4 and
the battery negative (-) lead when headlight leveling
switch ...
Check for intermittent
problems
1. CHECK FOR INTERMITTENT PROBLEMS
HINT:
For use of the intelligent tester only:
Inspect the vehicle's ECM using check mode.
Intermittent problems are easier to detect with an
intelligent tester when the ECM is in check mode. In
check mode, the ECM uses 1 trip detection logic, which
is more ...
