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
Radio Broadcast cannot be Received or Poor Reception
INSPECTION PROCEDURE
1 CHECK RADIO RECEIVER
Check the radio's automatic station search function.
Check the radio's automatic station search function
by activating it.
OK:
The ra ...
Vehicle Speed Signal Circuit between Radio Receiver and Combination
Meter
DESCRIPTION
This circuit is necessary for the ASL (Auto Sound Leveliser) built into the
radio receiver.
Speed signals are received from the combination meter and used for the ASL.
The ASL fun ...
Other materials:
Back-up Power Source Circuit
DESCRIPTION
This is the back-up power source for the A/C amplifier. Power is supplied
even when the ignition switch is
off and is used for diagnostic trouble code memory, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
(a) Remove the ECU-B fuse from the engine room juncti ...
Initialization not Completed
DTC C2177/77 Initialization not Completed
DESCRIPTION
Initialization is necessary after replacing any of the ECUs, tires with
different tire pressure, or tire pressure
warning valve and transmitter, after rotating the tires or when a new vehicle is
delivered.
WIRING DIAGRAM
INSPECTI ...
Seating configuration variation
Cargo capacity
Weight of the removed second
seat
If removing the second seats, it is possible to load extra cargo equal
to the weight of the removed seats.
(Cargo capacity) = (Total load capacity) - (Total weight of occupants) +
(Weight of the removed second seats)
Second seats w ...
