DSX-S300BTX - Sony Car Audio Service Manual (repair manual). Page 15

DSX-S300BTX

Note: The remote commander is necessary to check the test mode.
 

  (Operation is possible with a remote commander other than the one 

included with this set.)

Setting method:
1.  Press the [OFF] button to turn the power off.
2.  Press the [4] 

→ [5] → [1] buttons sequentially (the [1] button 

is pressed for two seconds).

3.  It is set to the test mode, and all segments of the EL indicator 

element light.

Releasing method:
Press the [OFF] button.

MICROPHONE  AUDIO  LOOPBACK
To confi rm the state of the external microphone/internal micro-
phone used when a handsfree function is used, the microphone 
audio is output from the speaker.
The breakdown judgment of the microphone can be done without 
connecting H/F with the cellular phone.

Procedure:
1.  Enter the test mode.
2.  Press the [SRC] button to select the Bluetooth Phone function.
3.  On/off of the microphone audio loopback function changes 

whenever the [2] button is pressed (The item of the “Loop-
Back” changes into “on”/“off”).

EXTERNAL/INTERNAL  MICROPHONE  CHANGEOVER
You can confi rm whether the internal and external microphones 
switch correctly.
The external microphone will be used when an external micro-
phone is plugged in to the MIC IN terminal.

Procedure:
1.  Enter the test mode.
2.  Press the [SRC] button to select the Bluetooth Phone function.
3.  Plug in the external microphone into the MIC IN terminal (The 

item of the “MIC” changes into “External”/“Internal”).

THE  EXTERNAL  MICROPHONE  DETECTION  
STATE  DISPLAY
Connected confi rmation of the external microphone detection line 
is done.
The trouble that doesn't change into an external microphone occurs 
when this detection circuit is broken.

Procedure:
1.  Enter the test mode.
2.  Press the [SRC] button to select the Bluetooth Phone function.
3.  The detection state of the external microphone is displayed in 

the EL indicator element (“Non” or “Detected” are displayed 
on the item of “MIC”).

 

In this state, when the external microphone is pulled out, the 
beep sound is output.