CMT-V50IP - Sony Audio Service Manual (repair manual). Page 4

UNLEADED  SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution:  Some printed circuit boards may not come printed with 

the lead free mark due to their particular size)

Unleaded solder has the following characteristics.
•  Unleaded solder melts at a temperature about 40 °C higher 

than ordinary solder.

 

Ordinary soldering irons can be used but the iron tip has to be 
applied to the solder joint for a slightly longer time.

 

Soldering irons using a temperature regulator should be set to 
about 350 °C.
Caution: The printed pattern (copper foil) may peel away if 

the heated tip is applied for too long, so be careful!

• Strong 

viscosity

 

Unleaded solder is more viscous (sticky, less prone to fl ow) 
than ordinary solder so use caution not to let solder bridges 
occur such as on IC pins, etc.

• 

Usable with ordinary solder

 

It is best to use only unleaded solder but unleaded solder may 
also be added to ordinary solder.

The laser diode in the optical pick-up block may suffer electro-
static break-down because of the potential difference generated by 
the charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also 
use the procedure in the printed matter which is included in the 
repair parts.
The fl exible board is easily damaged and should be handled with 
care.

NOTES  ON  LASER  DIODE  EMISSION  CHECK
The laser beam on this model is concentrated so as to be focused 
on the disc refl ective surface by the objective lens in the optical 
pickup block. Therefore, when checking the laser diode emission, 
observe from more than 30 cm away from the objective lens.

RELEASING  THE  DISC  SLOT  LOCK
The disc slot lock function for the antitheft of an demonstration 
disc in the store is equipped.

Releasing Procedure:
1.  Press the [

?/1

] button to turn the power on.

2.  Touch the [FUNCTION] sensor to turn the CD function.
3.  Touch the [x] sensor and press the [Z] button simultaneously 

for fi ve seconds.

4.  The message “UNLOCKED” is displayed on the liquid crystal 

display and the disc slot is unlocked.

Note: When “LOCKED” is displayed, the disc slot lock is not released by 

turning power on/off with the [?/1] button.

NOTE  OF  REPLACING  THE  MS-486  BOARD
When the MS-486 board is defective, exchange the LOADING 
ASSY (IM) (LOM1).

NOTE  OF  REPLACING  THE  TOUCH  KEY  BOARD
When the TOUCH KEY board is defective, exchange the TOP 
ASSY (TOP1).

IC801,  IC901,  IC902  AND  IC903  ON  THE  MAIN  BOARD
IC401, IC502, IC504, IC801, IC901, IC902 and IC903 on the 
MAIN board cannot exchange with single. When these parts are 
damaged, exchange the complete mounted board.

CHECKING  THE  OPERATION  AFTER  REPAIR
After repair completion, connect the “iPod” etc. corresponding to 
this unit, and check the operation of playback, recording, charge, 
etc.

TEST  DISCS
Use following TEST DISC (for CD) when this unit confi rms the 
operation and checks it.

Part No.

   

Description

3-702-101-01 DISC 

(YEDS-18), 

TEST

4-225-203-01 DISC 

(PATD-012), 

TEST

US

z

–

–

–

–

Canadian

z

–

–

–

–

AEP

–

z

z

–

z

Russian

z

–

–

–

–

Australian

z

z

–

–

–

Latin American

z

–

–

–

–

Brazilian

z

–

–

–

–

Singapore

z

–

–

–

–

Taiwan

–

z

–

–

–

Korean

–

–

z

–

–

Thai

–

z

–

z

–

HOW  TO  EJECT  THE  DISC  WHEN  POWER  SWITCH  
TURN  OFF
•  Refer to “SECTION 2. DISASSEMBLY”, remove the CD 

mechanism deck from the unit.