CX-LEM400, XR-EM400 - Sony Car Audio Service Manual (repair manual). Page 15

15

Checking Location: BD board (Side B)

+
–

BD board

TP (TE)

TP (VC)

oscilloscope

Traverse Waveform

0V

B

level: 1.0 

±

 0.5 Vp-p

Center of 
the waveform

A (DC 

voltage)

Traverse Waveform

0V

Tracking servo

Sled servo

ON

C (DC 
voltage)

Tracking servo

Sled servo

OFF

6.

Press the        

CD u

  button. (The trac

king servo and sledding

servo are turned ON)
Rotate RV101 on BD board and adjust the C (DC voltage) 
is almost equal to the A (DC voltage) in step 4. 

7. To exit from this mode, turn the power off.

• Always move the optical pick-up to most inside track when

exiting from this mode. Otherwise, a disc will not be unloaded.

• Do not run the sled motor excessively, otherwise the gear can

be chipped.

Procedure:
1.

Connect an oscilloscpe to test point TP (TE) and TP (VC) on
the BD board.

2.

While depressing the

CD u

  button, insert an AC plug to

enter the CD test mode.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Press the                   button. If it plays, press the             

CD u

again. (The tracking servo and the sledding servo are
turned OFF)

5.

Check the level B of the oscilliscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than 

±

 10%

CD u

  

 button

IC101

TP7
(VC)

IC103

RV101
E-F Balance
Adjustment

  TP8
(RFAC)

  TP6
(RFDC)

TP4
(FE)

TP2
(TE)