The service manual is really great - thanks to it I was able to install the laser unit and thus "save" my CD-player, which seemed to be impossible before I had the manual.
Complete service manual in very good scanning quality with all schematic and PWB graphics as well as assembly & maintenance instructions. A slight drawback is that the rastering of the PWB graphics sometimes makes it a bit difficult to follow fine traces, but no showstopper.
Text excerpt from page 7 (click to view)
2.4.
2.4.1.
How to Replace the Lithium Battery
Replacement Procedure
1. Remove the MAIN PCB. (Refer to Disassembly Procedures.) 2. Remove the Lithium battery (Ref. No. �Z9101� at component side of MAIN PCB) and then replace it into new one.
NOTE: This Lithium battery is a critical component. (Type No.: ML-421S/ZT Manufactured by Matsushita Battery Industrial Co.,Ltd.) It must never be subjected to excessive heat or discharge. It must therefore only be fitted in requirement designed specifically for its use. Replacement batteries must be of same type and manufacture. They must be fitted in the same manner and location as the original battery, with the correct polarity contacts observed. Do not attempt to re-charge the old battery or re-use it for any other purpose. It should be disposed of in waste products destined for burial rather than incineration.