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:
Data list / active test
1. READ DATA LIST
HINT:
Using the intelligent tester to read the Data List allows
the values or states of switches, sensors, actuators and
other items to be read without removing any parts. This
non-intrusive inspection can be very useful because
intermittent conditions or signals may be disco ...
Fold Lock Switch Circuit
DESCRIPTION
Each of the left and right seats has a fold lock switch that detects the lock
condition of the seat legs and
floor when the seat is in the stowed state. If the fold lock switch detects an
unlock condition, the 3rd SEAT
indicator on the combination meter will come on.
WIRING DIAGR ...
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 ...
