Editing Sega CD Service Manual

The document behind this page is titled, on its own cover, '''''MEGA-CD Maintenance Manual, Export''''' — with the inner title page reading '''''MEGA-CD Maintenance Manual, Europe''''' — dated '''August 1992, Rev. A''', 118 pages, Sega Enterprises, Ltd. It is the European/export manual for the first-generation [[Sega CD (Model 1)|Mega CD]]; the page title here uses the American name for the same machine.

It is by a wide margin the most complete Sega document on this wiki for the Model 1 unit, and it goes all the way down to PCB copper layers.

The scan carries a text layer.

== Contents ==

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:100%; text-align:left;"
! Section !! Page
|-
| 1. Block diagram || 
|-
| 2. Assembly drawing — 2-1 general reference number list || 4
|-
| 2-2. Assembly list: 1001 top case; 1002 side cover and side knob; 1003 side cover; 1004 CD-ROM unit shield; 1005 main board; 1006 CD drive unit and sub board; 1007 bottom shield and front cover || 5–19
|-
| 2-3. Procedure of disassembly and assembly || 20–31
|-
| 3. Spare parts list ||
|-
| 4. Accessories list ||
|-
| 7. IC pin assignments — main board IC1/IC2, IC3, IC6, IC7/IC8, IC10/IC11, IC13, IC14/IC15; sub board IC1, IC2, IC3/IC4/IC5 ||
|-
| 8. Parts list of PCB — 8-1 IC BD MEGA-CD MAIN BD EXPORT; 8-2 IC BD MEGA-CD SUB BD EXPORT; 8-3 ASSY MEGA-CD CONNECT BD EXPORT || 84–96
|-
| 9. Schematic diagram — 9-1 main board; 9-2 sub board; 9-3 connect board || 91–103
|-
| 10. Mount diagram — component side and solder side for all three boards || 104–109
|-
| 11. PCB design spec — copper layer artwork, component side and solder side, for all three boards || 110–115
|}

== What this manual settles ==

* '''The Mega CD Model 1 is three boards, not one''': a '''main board''', a '''sub board''' and a '''connect board'''. Each has its own parts list, its own schematic and its own mount diagram. A capacitor list for this machine that does not say which board a designator belongs to is ambiguous.
* '''The IC complement of the main board''', with pin assignments for each: IC1/IC2 HD68HC000CP-12 and the Sega custom '''MCE2 MB634120, part 315-5548'''; IC3 custom '''RF5C164A, part 315-5476A'''; IC6 MB3790; IC7/IC8 TC511664BZ-80; IC10/IC11 TC51832FL-10; IC13 LC8951; IC14/IC15 MB8464A-80. On the sub board: IC1 LC7883KM, IC2 LC7881M-C, IC3/IC4/IC5 µPC844G2.
* '''The Model 1 boards use a plain interleaved <code>C</code> sequence with no <code>CE</code> series''' — C1 through C58 in one run, with the electrolytics named in the description column (for example C41–C50 are 10 µF 16 V, Sega 150-0400 / 150-0400-01, and C51/C52 are 100 µF 6.3 V radial, 150-0401). This matches the [[Mega Drive Maintenance Manual - PAL-G, August, 1992, Rev. A|Mega Drive Model 1]] convention, not the Model 2 one.
* '''Two part numbers are given for the same position''' in places — 150-0400 and 150-0400-01 for C41–C50 — which is Sega recording a second approved vendor, not a contradiction.

== What this manual does not contain ==

* '''No fault tree or symptom table.''' This is a maintenance and parts manual: assemblies, disassembly, parts, schematics and board artwork. It does not tell you what a symptom means.
* '''No CD drive alignment or adjustment procedure.'''
* '''No Model 2 coverage.''' For the [[Sega CD (Model 2)]] see the [[Sega CD 2 / Mega CD 2 - Service Manual]].
* Export/Europe machine only.

== Pages that cite this document ==

* [[Sega CD (Model 1)]]
* [[Sega CD (Model 1) Maintenance Guide]]
* [[Sega CD (Model 1) Troubleshooting Guide]]
* [[Sega CD (Model 1) Capacitor Replacement Guide]]

<pdf> File:Sega CD Service Manual.pdf </pdf>

Download: [[:File:Sega CD Service Manual.pdf|Sega CD Service Manual.pdf]]

[[Category:Sega Service Manuals]]
[[Category:Service Manuals]]