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Sega Master System II Service Manual

April 1991 Sega Enterprises, Ltd. Overseas Consumer Products Division

General

1. PRODUCT NUMBER AND COLOR SPECIFICATIONS

TerritoryModel No.Color FormatSystemRF ModulatorChannel
AmericaMK-3006NTSCM200-5118-01 or 200-51153/4
CanadaMK-3006-22PALB (VV)200-5194-023/4
AustraliaMK-3006-03PALB(VE)200-51980/1
N. ZealandMK-3006PALD200-51392/3
ChinaMK-3006-15PALG200-5086-023/4
GermanyMK-3006-18PALG200-5086-0236
FranceMK-3006-09PALRGBNONE-

2. AC ADAPTOR SPECIFICATIONS

TerritoryParts Model No.NumberDiagram NumberVoltage/FrequencyPlug Type
AmericaMK-3006400-5115H-0246AC 120 V + 10%/ 60HzA Type
CanadaMK-3006-22400-5123H-0249AC 120 V + 10%/ 60HzA Type
AustraliaMK-3006-03400-5050H0133AC240V + 10%/ 50HzS Type
N. ZealandMK-3006-04400-5050H-0133AC240V + 10%/ 50HzS Type
ChinaMK-3006-15400-5093-91H-0158-01AC220V + 10%/ 50HzA Type
GermanyMK-3006-18400-5126 AC220V + 10%/ 50HzC Type

3. PRODUCT DIMENSIONS AND WEIGHT

Main Unit Dimensions
256 (W) x 172 (D) x 81.5 (H) mm
Main Unit Weight
790 g
Packed Dimensions
360 (W) x 216 (W) x 125 (H) mm
Packed Weight
1.7 kg.
Master Carton Dimensions
(6 pcs./carton) 450 (W) x 400 (D) x (390 (H) mm
Master Carton Weight
11.5 kg. (0.072 m3)

4. ELECTRICAL SPECIFICATIONS

Power
AC 220V or 240V, 50Hz
CPU
Z-80A 3.58 MHz
RAM
64 Kbit
V-RAM
128 Kbit
ROM
1Mbit
Scrolling Screen
256 x 192 dot
32 colors displayed from a palette of 64
Sprite Screen
64 sprites of 8 x8 dot or 8 x 16 dot on screen
16 colors displayed from a palette of 64
Character Patterns
Maximum of 448 types
Scrolling Directions
Horizontal, Vertical, Diagonal
Sound
Three types plus noise

Repair Procedures

1. Flowchart For Troubleshooting Fault Locations

Power switch check
 |
 v
IC8 OUT +5V check
 |<------- Reset circuit check
 v
XTAL 10.738 MHz output clock <-- IC4; pin41
 |
 v
IC1: pin6 clock 2.58 MHz check
 |
 v
IC2: pins 20, 22, pulse IN check
 |
 v
IC3: pins 1, 20, 22, 27 pulse check
 |
 v
IC5: RGB signal. C. SYNC signal check; Audio signal check
 |
 v
IC6, IC7: pins 20, 22, 27 pulse check
 |
 v
IC9: pins 1 to 2, 3, 4, RGB IN check; pin 19 to 20, C. VIDEO OUT check
 |
 v
RF modulator IN check; RF modulator OUR (+ 5 V) check

2. MAIN UNIT (POWER BASE)

(A). Servicing the Main Unit (Power Base)

NS=10-9s

Parts Test Procedure

Fault Location

Symptoms

1. IC 8 (LM7805) power chcck.

  1. INPUT DC 9V
  2. OUTPUT Vcc=DC5V
  1. IC8 (LM7805) faulty.
  2. Soldering Faulty.
  3. Short Circuit
  4. Printed circuit board (PCB) pattern is cut.
  5. POWER switch is faulty.
  6. Heat sink attachment faulty.
  1. LED doesn't light.
  2. No picture

2. Power check of ICs

  1. Is Vcc 5V power present?
  1. PCB pattern is cut.
  2. Soldering is faulty.
  1. No picture.
  2. Screen is black.

3. Is reset circuit operating?

  1. Use tester to measure voltage of JR. Should be 0-3.6 V (slowly rises).
  1. Capacitor C18 faulty.
  2. Soldering faulty.
  3. Resistor R4 faulty.
  1. No picture.
  2. Screen is black.

4. Is oscillator circuit working?

  1. Pin 41 of IC4: AC 6 Vp-p; 10.738635 MHz ± 100Hz
  2. Pin 33 of IC 5 clock 3.579545 MHz ± 30 Hz
  3. Pin 42 of IC4 clock:4.43361875 MHz ± 30Hz
  1. OSC(53M) faulty
  2. Soldering faulty
  3. PCB pattern is cut
  4. IC 4 is faulty
  5. Frequency exceeds allowable deviation.
  1. No picture
  2. Color may be monochromatic

5. Check conncctors

  1. Make visual check of connector pins.
  2. Check for faulty soldering connections
  1. Broken from excessive weight.
  2. Soldering faulty.
  3. PCB pattern is cut.
  4. Terminal plugs are dirty.
  1. No picture
  2. Picture is monochromatic.
  3. Characters are unnatural.
  4. Controls do not respond properly.

6. Check button switches.

  1. Check power button switch.
  1. Switch is loose.
  2. Soldering faulty.
  3. PCB pattern is cut.
  4. Switch is short-circuited.
  1. No power voltage present.
  2. LED doesn't light.
  3. No picture.
  4. Reset occurs spontaneously.
  5. Characters suddenly appear abnormal.
  1. Check Pause button switch
  1. Soldering faulty
  2. PCB pattern is cut
  3. Blade is not parallel with circuit board.
  4. Switch is short-circuited.
  1. Pause doesn't operate properly.

7. Check RF modulator

  1. Is OUT +5V present?
  1. PCB pattern is cut.
  2. Soldering is faulty.
  3. RF modulator is faulty.
  4. IN event IC9 is faulty.
  1. No picture
  2. Picture appears dirty.
  3. No sound.
  4. Much audio noise.
  1. Check channel selector: Are CH3 and CH4 ok?
  1. RF modulator is faulty.
  1. CH3 appears, but not CH4.
  2. CH4 appears, but not CH3.

(B) Possible symptoms for cach fault location

Fault Location (Contents of malfunction) Symptom
1. When IC1 (CPU) is faulty.
  1. System doesn't operate at ail. No picture at all.
2. When IC2 (OS ROM) is faulty.
  1. Since this is the program which operates the system, no picture will appear.
  2. Depending on the case, a mosaic pattern may appear.
3. When IC3 RAM is faulty.
  1. Since this is the unit that temporarily records data, no picture will appear.
  2. Depending on the case, a picture may appear, but it is easily distorted.
4. When 1C4 is faulty.
  1. Since this IC emits several control signals, no picture will appear.
  2. Controller may not respond properly.
  3. Pause, reset may not respond properly.
  4. If no oscillation is present, clock 3.5S MHz is not produced, with result that system does not operate at all; no picture will appear.
5. When IC5 is faulty.
  1. In addition, several control signals are involved; if fault is present, system will not operate and no picture will appear.
  2. Even if a picture appears, characters may be distorted.
  3. Colors may be improper.
  4. Sound may appear alone without picture.
  5. Picture may appear alone without sound.
6. When IC6, IC7 are faulty.
  1. Since these parts arc responsible for temporarily storing color data, picture may not appear.
  2. Even if picture appears, colors may be improper.
  3. Characters may be distorted.
  4. Picture may be move sluggishly or jerkily.
7. When IC8 is faulty.
  1. Since this is +5 V stabilized current, if malfunction is present, uniform +5 V is not present; system will not operate and no picture will appear.
  2. LED doesn't light.
8. When IC9 is faulty.
  1. Since this part converts the RGB signal to composite mode, a malfunction will result in no picture.
  2. Even if a picture appears, color may be abnormal.

(C). In the event picture appears alone without sound

Service Procedures Fault Location
  1. Is audio signal output from pin 15 of IC5?
    1. MAX 300 mVp-p
    2. 20 Hz-20kHz
  1. Soldering is faulty.
  2. PCB pattern is cut.
  3. Q48, Q49, R47 are faulty
  4. R46 is faulty
  5. IC5 is faulty.
  6. RF modulator is faulty.

(D) In event picture is not present.

Service Procedures Fault Location
  1. Is video signal present at pin 3 of RF modulaor?
  2. Is video signal output from pons 19 and 20 of IC9?
  3. Is RGB signal present at pins 1,2,3, and 4 of IC9?
  1. C38, R29 is absent or faulty.
  2. Soldering faulty.
  3. PCB pattern is cut.
  4. RF modulator is faulty (when picture is present on RF).
  5. IC9 is faulty.
  6. Peripheral parts around IC9 are faulty.

(E) In event controls do not respond normally

Symptom(s) Fault Location(s)
  1. Game doesn't start.
  2. Button may not respond when pressed.
  3. Absolutely no response at all.
  1. CON2 or CON3 faulty (disconnection)
  2. Soldering faulty.
  3. PCB pattern is cut.
  4. IC is faulty.
  5. EMI filter is faulty.
  6. Resistor 330 ohm is faulty.
  7. Check for continuity between CON2 and CON3 terminals and terminals of IC4.
  1. Demonstration screen doesn't appear.
  2. Switch stays depressed in middle of game.
  3. Switch remains fixed in one direction.
  4. Starts by itself.
  1. CON2 or CON3 is faulty (short-circuited)
  2. Soldering is short-circuited.
  3. PCB pattern is short-circuited.
  4. IC4 is faulty.

3. SOFTWARE

Software (Card or Cartridge) Malfunctions

Symptom Fault Location
  1. No picture. Picturc remains monochromatic. Picture is mosaic pattern.
  1. Connector (50 pin) is dirty, disconnected, or other connection fault.
  2. Soldering faulty.
  3. Short-circuit.
  4. Capacitor is missing or faulty.
  5. IC is damaged from overheating or static electricity.
  1. Characters arc disrupted suddenly in middle of game. Reset occurs spontaneously in middle of game. Other abnormal symptoms appear in middle of game.
  1. Connection fault at connector (50 pin).
  2. Soldering faulty.
  3. Capacitor is missing or faulty.
  4. IC runaway overheating.
  5. In the case of number 4 above, the problem may be rcctificd by adding a capacitor 100PF--180PF at A13 (address 13).
  6. IC is faulty.

4. AUTO SWITCHBOXES

Symptoms Fault Location
  1. No picture. Game piclurc doesn't appear. TV picturc doesn't appear.
  1. Cable is cut or shorted.
  2. Plug is faulty.
  3. Soldering is faulty on cable connection terminal.
  4. PCB pattern is broken or interrupted.
  5. Auto-switcher unit is faulty.
  1. Sound is bad. Much audio noise.
  1. Cable is cracked.
  2. Soldering faulty.
  3. Plug connection is faulty.
  4. Auto switcher is faulty (adjustment faulty).

5. CONTROLLER RELATED

Control pads

Symptoms Fault Location
  1. Controller docs not operate. Doesn't move as it should. Game doesn't start.
  1. Cable is cut.
  2. Faulty connection at connector.
  3. PCB pattern is cut.
  4. Conductive rubber is faulty.
  5. Soldering faulty.
  1. Moves spontaneously by itself
  2. Switch remains depressed in one direction.
  1. Cable is shorted.
  2. Solder is greasy.
  3. Conductive rubber is stuck.

Diagrams and Parts Lists

Schematic Diagram For Master System II PAL Version

IC BD M4JR PAL 171-5922A

IC BD M4JR PAL-G 837-7367

IC BD M4JR PAL-I 837-7369

IC BD M4JR PAL-B (VV) 837-7370

IC BD M4JR PAL-B (VE) 837-7371

IC BD M4JR PAL-D 837-7559

Parts List For Master System II PAL Version

LOCATIONPART NUMBERDESCRIPTION
AC ADAPTOR400-5130AC ADAPTOR AC240-/DC9V 0.5A (Australia)
AC ADAPTOR400-5126AC ADAPTOR AC 220V/DC9V 0.5A (Europe)
AC ADAPTOR400-5129AC 240V/DC9V 0.5A(UK)
RF. MOD.200-5091-ARF MODULATOR UB 3622 (I-PAL)
RF. MOD.200-5198RF MODULATOR VE 3423 (B-PAL VE)
RF. MOD.200-5086RF MODULATOR UE 3622 (G-PAL)
 610-5127ASSY CONTROL PAD 3020-03
 610-5128ASSY RF SW BOX W/RF CABLE
 671-1215SUPPORT BOARD MS2 MULTI
 601-6681STYROFOAM MS2 MULTI UR
 671-1155BOXC MS2 BLACK MULTI
 671-1156MA CTNMS2 MULTI
 672-0228INSTR MANUAL M4 JR. MULTI
 253-6426-01BOTTOM CASE M4 JR. BLACK PAL
 250-5185TOP SHIELD M4 JR.
 250-5186BOTTOM SHIELD M4 JR.
 253-6425TOP CASE M4 JR. BLACK
 253-6352DOOR M4 JR.
 253-6427PAUSE SW MR JR. BLACK
 253-6428POWER BUTTON M4 JR. BLACK
PCB171-5922APC BD M4JR PAL
HOLDER250-5187HOLDER M4JR
CN1209-5023EDGE CONN 50P PSB4D25S-4R1
CN2209-5017D-SUB CONN 9P
CN3209-5017D-SUB CONN 9P
CN4212-5004PIN PLUG FOR DC/NP UC-0056 #1
POWER SW509-5240-01SLIDE SW HSW1699-01-010
PAUSE SW509-5207TACT SW SKEVAA
PAUSE SW510-5019TACTILE PUSH SW SKEVAA
IC1315-0041ICZ80A
IC2MPR-12808IC OS 1M MASK M4 JR
IC3315-0298IC UPD4168C-20
IC4315-5237IC GA UPD65005C-114
1C5315-52461C CUSTOM CHIP UPD9004G
IC6, IC7315-0298-15IC UPD4168C-15
IC8313-0092IC MA7805UC
IC9313-5067ICCXA1145P
D1481-0149-01DIODE 1S2473
D2481-5038-01DIODE 1SR-35-100A
LI180-5033PEAKING COIL 12 UH
L2, L3180-5032PEAKING COIL 100UH
Rl, R2479-0472RES 4.7KOHM 1/6 W
R9479-0472RES 4.7 KOHm 1/6 W
Rll, R22, R24, R25479-0102RES 1 KOHM 1/6 W
R4479-0104RES 100 KOHM 1/6 W
R5, R6479-0331RES 330 OHM 1/6 W
R7, R8479-0331RES 330 OHM 1/6 W
RIO479-0332RES 3.3 KOHM 1/6 W
R12, R14, R16, R28479-0822RES 8.2 KOHM 1/6 W
R13,R15, R17479-0821RES 820 OHM 1/6 W
R18, R20, R29479-0222RES 2.2 KOHM 1/6 W
R19, R30479-0152RES 1.5 KOHM 1/6 W
R21479-0202RES 2 KOHM 1/6 W
R26479-0273RES 27 KOHM 1/6 W
R27479-0103RES 10 KOHM 1/6 W
CI, C2, C3, C4, C5, C6, C9, CIO, Cll, C12, C13, C25, C53151-0126CAP CER 82PF 50V
CI, C8, C19, C23, C45, C46, C47, C48, C49151-0020CAP CER 33PF 50V
C14, C17151-0021CAP CER 20PF 50V
C15151-0002CAP CER 100PF 50V
C16, C21, C22151-0018CAP CER RA 150PF 50V
C18, C32, CEl, CE2, CE3, CE4, CE5, CE6150-0023CAP E 10UF 16V
C20, C50151-0072CAP CER 51PF 50V
C24151-0156CAP CER 270PF 50V
C26, 34151-0011CAP CER 0.01 UF 50V
C27, C28, C29, C39, C40, C54151-0060CAP CER 0.1 UF 16V
C30151-0075CAP CER RA 180PF 50V
C31150-0009CAP E 1UF 50V
C33, C35151-0190CAP CER 12PF 50V
C36151-0159CAP CER RA 100PF 50V
C37151-0172CAP CER 180PF 50V
C38, C42, C43150-0047CAP E 100UF 10V
C41150-0059CAP E 100UF 16V
C44150-0062CAP E 47UF 10V
C51151-0287CAP CER 27PF 50V
C52151-0079CAP CER 47PF 50V
CPl, CP2, CP3, CP4, CP5, CP6, CP7, CP8, CP9, CPIO, CP11, CP 12, CPl3151-0170CAP CER AX 0.022UF 16V
FBI, FB2, FB3, FB4, FB5, FB6, FB8, JV, JG271-0005-1BEADS INDUCTOR FBA04VA600VB-00
FB7270-5027LINE FILTER
FB9, FBIO270-5035LINE FILTER FBR07HA121
EM11, EM12, EM13, EM14, EM15, EM16, EM18, EM21, EM22, EM23, EM24, EM25, EM26, EM28271-0007EMI FILTER STX222MB
EM 17, EM27271-0006EMI FILTER STB271KB
OSC230-5058OSC 53.203424M 20PPM
RA1477-0005RES PACK 8*4.7K (RA8-4728K)
GRS601-0076TML JNT CMPD 200G/TUBE (AMICOM)

Schematic Diagram For Master System II RGB Version

IC BD M4 Jr. RGB 171-5926

IC BD M4JR RGB 837-7560

Parts List For Master System II RGB Version

LOCATIONPART NUMBERDESCRIPTION
 610-5127ASSY CONTROL PAD 3020-03
 400-5048YAC ADAPTOR AC220V/DC9V 1A
 610-0130RGB BOX FRANCE
 671-1215SUPPORT BOARD MS2 MULT1
 601-6681STYROFOAM MS2 MULTI UK
 671-1155BOX MS2 BLACK MULTI
 671-1156MA CTNMS2 MULTI
 672-0228INSTR MANUAL M4 JR. MULTI
 253-6426-02BOTrOM CASE M4 JR. BLACK RGB
 250-5185TOP SHIELD M4 JR.
 250-5186BOTTOM SHIELD M4 JR.
 670-0835SEAL SER. NO. M4 JR. RGB
 253-6425TOP CASE M4 JR. BLACK
 253-6352DOOR M4 JR.
 253-6427PAUSE SW MR JR. BLACK
 253-6428POWER BUTTON M4 JR. BLACK
PCB171-5926APC BDM4JRVA1
CN1209-5023EDGE CONN 50P PSB4D25S-4R1
CN2, CN3209-5017-01D-SUB 9P ANGLE TYPE UC-0060 #2
CN4221-5004PIN PLUG FOR DC/NP UC-0056#1
CN5212-5106DIN CONN B-TYPE UC-0059#2
POWER SW509-5240-01SLIDE SW HSW1699-01-010
PAUSE SW509-5207TACT SW SKEVAA
PAUSE SW510-5019TACTILE PUSH SW SKEVAA
IC1315-0041ICZ80A
IC2MPR-12808ICOS 1MMASKM4JR
IC3315-0298IC UPD4168C-20
IC4315-5216IC CUSTOM CHIP G/A
IC5315-5246IC CUSTOM CHIP UPD9004G
IC6, IC7315-0298-15IC UPD4168C-15
1C8313-0092IC MA7805UC
D1481-0149-01DIODE 1S2473 RADIAL
D2481-5038-01DIODE 1SR-35-100A RADIAL
Rl, R2479-0472RES 4.7 KOHM 1/6 W
R3479-0104RES 100 KOHM 1/6 W
R4479-0472RES 4.7 KOHM 1/6 W
R5, R6479-0331RES 330 OHM 1/6 W
R7, R8479-0331RES 330 OHM 1/6 W
R59479-0152RES 1.5 KOHM 1/6 W
R60, R61479-0222RES 2.2 KOHM 1/6 W
C1150-0062CAPE 47UF 10V
C2150-0023CAPE 10UF 16V
C3, C4151-0279CAP CER 56PF 50V
C50150-0059CAPE 100UF 16V
C51, C52150-0060CONN 0.22MF 16V
C53, C54150-0047CAPE 100UF 10V
C55151-0060CAPCER 0.1 UF 16V
C61151-0075CAPCERRA 180PF 50V
C72151-0159CAPCERRA 100PF 50V
CPl, CP2, CP3, CP4, CP5, CP6, CP7, CP8, CP9,151-0170CAPCER AX 0.022UF 16V
CEl, CE2, CE3, CE4, CE5, CE6150-0023CAPE 10UF 16V
FBI, FB2, FB51, FB55, FB56, FB67, JV, JG, JPR, JPG, JPB, JPS,271-0005-1BEADS INDUCTOR FBA04VA600VB-00
X'TAL230-0046-1XTAL 10.738635
EM11, EM12, EM 13, EM 14, EM 15, EM 16, EM18, EM21, EM22, EM23, EM24, EM25, EM26, EM28271-0007EMI FILTER STX222MB
EM 17, EM27271-0006EMI FILTER STB271KB
JP1600-5061JUMPER WIRE 5MM
HOLDER250-5187HOLDER M4JR
GRS601-0076TML JNT CMPD 200G/TUBE (AMICON)
S-LOCK090-0012SCREW LOCK
CN2L, CN2R, CN3L, CN3R012-0306 TAP SCR PH 3*6
7805-HOLDER029-0214S-T1TE SCR PH M3*8
CN1L, CN1R048-0001EYLET 3.5*7
DINHOLDER250-5013DIN CONN HOLDER



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