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Sharp MZ-2200 Troubleshooting Guide

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Sharp MZ-2200 system configuration (Sharp brochure)
Sharp's MZ-2200 system chart: data recorder, displays, disk drives, printers and options (Sharp brochure)

Fault-finding on the Sharp MZ-2200 starts outside the case, with the monitor, the MZ-1T02 data recorder and their cables, because the MZ-2200 has neither built in. No MZ-2200 service manual or circuit diagram is known to be online; for checks inside the computer, the MZ-2000's owner's manual is the nearest documented design, and its use is described in the Sharp MZ-2000 Troubleshooting Guide.[1]

Warning: unplug the MZ-2200 before opening the case. The external monitor contains high voltages; see CRT Discharge Procedure before opening it.

Quick reference

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Symptoms, causes and actions
Symptom Probable cause Action
No picture Monitor on the wrong output, cable, monitor fault No picture
MZ-2000 graphics appear blue only, or in odd colours No palette on the MZ-2200 Things that are not faults
Tape does not move or will not load MZ-1T02 cables, pinch roller, head MZ-1T02 data recorder
Completely dead Mains, fuse or power supply No power
Powers up, no start-up message Supply rail missing, logic fault No start-up

[1][2]

No picture

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The MZ-2200 has two video outputs at the back: a digital RGB output for a colour monitor and a separate monochrome output.[2][1]

  1. Check that the monitor is on the output that suits it, and try the other output with a monitor of that type.
  2. Press the IPL button in the front pocket to run the initial program loader again, or RESET to restart the machine.[2]

A colour monitor such as Sharp's MZ-1D15 (14-inch) connects to the RGB output.[2]

MZ-1T02 data recorder

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The MZ-1T02 is the only recorder the MZ-2200 can use. It takes both power and signals from the MZ-2200, through a square four-pin plug and a 16-pin plug, and has no mains lead.[3]

  • Recorder completely dead, no lamps and no motor on rewind: check that the four-pin power plug is fully home, with the MZ-2200 switched on.[3]
  • Rewind and fast forward work but loading fails: check the 16-pin signal plug, then clean the head.[3]
  • Tape stops, slips or is chewed: inspect the pinch roller, which can melt with age.[3][1]
  • READ lamp does not light when a load starts: recheck the 16-pin signal plug.[3]

No power

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  1. Check the mains lead and the power switch at the left of the rear panel.[2]
  2. Unplug, open the case and check the supply's fuses. The supply is at the rear right under a perforated metal cover.[4] Its circuit has not been published online; on the MZ-2000, the equivalent supply has a 1 A mains fuse and 2 A fuses on the +5 V and +12 V regulators, described under No power and No start-up in the MZ-2000 guide.
  3. If the fuse has blown, check the electrolytic capacitors on the primary side of the supply before fitting a new fuse. Ohishi Nobuaki, writing about power supply recapping, notes that on the MZ-2200 a primary-side electrolytic that had lost capacitance made the fuse blow.[5]
  4. Disconnect the MZ-1T02 and any expansion cards and try again. The MZ-2200's supply powers the recorder and, because the expansion unit has no supply of its own, the expansion cards too.[1][3]

No start-up

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If the computer powers up but nothing appears on a known-good monitor:

  • Measure the supply rails on the main board. On the MZ-2000 they are +5 V, +12 V and −5 V at the CPU board's power connector, with +15 V also produced by the supply.[6] Confirm the MZ-2200's connector pinout from its wiring before relying on that.
  • Remove any expansion cards and try again.
  • Do not expect the MZ-2000's start-up messages word for word: Sharp changed the strings in the MZ-2200's IPL ROM.[1]

The main boards of the two machines appear to be close: one owner brought a failed MZ-2000 back by fitting a main board said to have come from an MZ-2200.[7] The MZ-2000's circuit diagrams can therefore help to trace a fault, with care, using the Sharp MZ-2000 Owner's Manual.

Things that are not faults

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  • MZ-2000 software that draws on one graphics page appears entirely in blue on a colour monitor, and software that uses several pages shows them combined in the colour of each plane, which can look psychedelic or flicker. The MZ-2200 has no colour palette.[1]
  • Some tapes released after the MZ-2200 carry a colour version for the MZ-2200 on one side and a monochrome MZ-2000 version on the other; load the side that suits the monitor.[1]
  • Reverse video shows on a green monitor but not on a colour one.[1]
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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 MZ-2000, Wikipedia (Japanese)—link(accessed 2026-10-21) Section "MZ-2200": the same basic specification as the MZ-2000 and full software compatibility; computer, display and data recorder separated; colour and monochrome CRT interfaces and a cassette interface for the MZ-1T02 only; the IPL ROM's messages and some routines differ from the MZ-2000's; no palette, so MZ-2000 software using one graphics page appears all in blue on a colour monitor, and software using several pages shows them combined in each plane's colour, which can look psychedelic or flicker in several colours; some later tapes carried a colour MZ-2200 version on one side and a monochrome MZ-2000 version on the other; reverse video works on a green monitor but is ignored on a colour one; the MZ-1T02's pinch roller melts with age.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 パソコン戦国時代に第一線で走り続けた「シャープ MZ-2200」– Sasaki Jun, AKIBA PC Hotline! (Impress), 1 June 2021—link(accessed 2026-10-21) Rear panel from the left: power switch, MZ-1T02 power socket, MZ-1T02 signal socket, digital RGB output and monochrome output, with the expansion unit below; colour display possible from the start with a colour monitor such as the MZ-1D15 (14-inch, 72,000 yen); front pocket with RESET, IPL and volume slider; graphics board and memory equivalent to the MZ-1R01 and two MZ-1R02 fitted as standard; the case opens like a car bonnet after the screws are removed.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 さまざまなメーカーから数多くの機種が登場したデータレコーダたち ～シャープ編～– Sasaki Jun, AKIBA PC Hotline! (Impress), 16 January 2024—link(accessed 2026-10-21) The MZ-1T02 works only with the MZ-2200 and no other recorder works with it; front keys REW, FF, STOP and EJECT with a tape counter; READ lamp while loading and WRITE lamp while saving; a 16-pin data cable and a square 4-pin power cable, with no AC connection; the pinch roller can melt with age, so check it first on a second-hand unit.
  4. ↑ AKIBA PC Hotline!, "パソコン戦国時代に第一線で走り続けた「シャープ MZ-2200」" (1 June 2021), photograph of the opened case (image asharpmz3), article page: power supply at the rear right under a perforated metal cover, main board left of centre.
  5. ↑ MZ-1500– Ohishi Nobuaki, Nibbles lab. Sharp museum—link(accessed 2026-10-21) Section on replacing the power supply capacitors: power supplies usually fail through electrolytic capacitors losing capacitance; in some circuits loss of capacitance in a primary-side electrolytic makes the fuse blow, "as it did on the MZ-2200" (MZ-2200がそうだった); swelling is not always visible, so Ohishi replaces every electrolytic in a supply.
  6. ↑ Sharp, MZ-2000 Owner's Manual (Japanese) (File:Sharp MZ-2000 Owner's Manual.pdf), figure 4-15, CPU board (5), printed page 67 (PDF page 68), and figure 4-18, power circuit, printed page 70 (PDF page 71): CN7 on the MZ-2000's CPU board with −5 V, +12 V, +5 V and GND; supply outputs +15 V, +12 V, GND, +5 V and −5 V.
  7. ↑ MZ-2000モニタ交換計画, Nibbles lab. (Ohishi)—link(accessed 2026-10-21) A main board said to have been taken from an MZ-2200 was fitted to a failed MZ-2000, and the IPL message then appeared.


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