Apple macintosh iisi Service Manual

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Macintosh IIsi

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Basics

Macintosh IIsi

Basics Overview - 1

Overview

This manual contains
complete repair procedures
for the Macintosh IIsi
shown at left.

Figure: Macintosh IIsi

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Specifications

IIsi

Specifications Processor - 1

Processor

CPU

Coprocessor

Motorola 68030 microprocessor
20 MHz
32-bit internal data bus
256-byte instruction and data caches
Burst-mode RAM access
Built-in memory management unit (MMU)

Motorola 68882 floating-point unit (FPU) included on the

optional adapter card

20 MHz

Specifications Memory - 2

Memory

RAM

ROM

PRAM

2 MB, expandable to 17 MB

512K standard

256 bytes of parameter memory

Specifications Disk Storage - 3

Disk Storage

Floppy Drive

Hard Drive

Internal 1.4 MB floppy drive

Internal 40 MB hard drive
Optional internal 80 MB hard drive

Specifications I/O Interfaces - 4

I/O Interfaces

Expansion

SCSI

Serial

One slot for either a NuBus or 030 direct slot card
Power available (15 W maximum)
+ 5 V 2.0 A
+12 V 175 A

-12 V 150 A

One external SCSI port; DB-25 connector

Two RS-422/RS-232/AppleTalk serial ports; mini DIN-8

connectors

Specifications I/O Devices - 5

I/O Devices

Keyboard

Mouse

Apple Keyboard, Apple Keyboard II, or Apple Extended Keyboard

connected through Apple Desktop Bus (ADB) ports (mini
DIN-4)

ADB mouse (mini DIN-4)

Specifications Sound and Video - 6

Sound and Video

Sound Generator

Output impedance of 8–600 ohms
Short-circuit protected
Disables internal speaker when in use
Four-voice, wavetable synthesis and stereo sampling generator

Specifications Electrical - 7

Electrical

Line V oltage

Frequency

Maximum Power

100–240 VAC, automatically configured

50–60 Hz, single phase

100 W (not including monitor)

Specifications Physical - 8

Physical

Dimensions

Weight

Height: 4.0 in. (10 cm)
Width: 12.4 in. (31 cm)
Depth: 14.9 in. (37.2 cm)

10 lb. (4.5 kg)
Configuration of RAM, floppy drives, hard drives, and NuBus

expansion cards will vary weight.

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Troubleshooting

IIsi

Troubleshooting General/ - 1

General

The Symptom Charts included in this chapter will help you
diagnose specific symptoms related to your product. Because cures
are listed on the charts in the order of most likely solution, try
the first cure first. Verify whether or not the product continues to
exhibit the symptom. If the symptom persists, try the next cure.
(Note: If you have replaced a module, reinstall the original module
before you proceed to the next cure.)

If you are not sure what the problem is, or if the Symptom Charts
do not resolve the problem, refer to the Flowchart for the product
family.

For additional assistance, contact Apple Technical Support.

Troubleshooting Symptom Charts/Video - 2

Symptom Charts

Video

Screen is dark, audio
and at least one drive
operate, fan is
running, and LED is
lit

1 Adjust brightness on monitor.
2 Verify monitor works with different Macintosh.
3 Replace monitor. Refer to appropriate monitor manual to

troubleshoot defective monitor.
4 Replace video cable.
5 Replace video card.
6 Replace SIMMs. See Hardware/Memory.
7 Replace logic board. Retain customer’s SIMMs.
8 Replace power supply.

Troubleshooting Symptom Charts/Video

(Continued)

- 3

Screen is dark, audio
and drive do not
operate, but fan is
running and LED is lit

Partial or whole
screen is bright and
audio is present, but
no video information
is visible

Video

1 Verify monitor works with different Macintosh.
2 Replace video cable.
3 Replace monitor. Refer to appropriate monitor manual to

4 Remove NuBus cards.
5 Remove peripherals.
6 Replace SIMMs. See Hardware/Memory.
7 Replace logic board. Retain customer’s SIMMs.
8 Replace power supply.

1 Verify monitor works with different Macintosh.
2 Replace monitor. Refer to appropriate monitor manual to

3 Replace video cable.
4 Replace logic board. Retain customer’s SIMMs.

(Continued)

troubleshoot defective monitor.

troubleshoot defective monitor.

Troubleshooting Symptom Charts/Video

(Continued)

- 4

Screen is completely
dark, fan is not
running, and LED is
not lit

Video

1 Plug the monitor directly into a wall socket and verify that

2 Remove NuBus card and switch on power again. (NuBus card

3 Remove peripherals.
4 Replace power supply.
5 Replace logic board. Retain customer’s SIMMs.

(Continued)

the monitor has power.

draws more than 45 watts.)

Troubleshooting Symptom Charts/Floppy Drive - 5

Floppy Drive

Audio and video
present, but internal
floppy drive does not
operate

Disk ejects; display
shows Mac icon with
blinking “X”

Disk will not eject 1 Switch off computer. Hold mouse button down while

1 Replace internal floppy drive cable.
2 Replace internal floppy drive.
3 Replace logic board. Retain customer’s SIMMs.

1 Replace floppy disk.
2 Replace internal floppy drive cable.
3 Replace internal floppy drive.
4 Replace logic board. Retain customer’s SIMMs.

switching computer on.
2 Eject disk manually.
3 Replace floppy drive.

Troubleshooting Symptom Charts/Floppy Drive

(Continued)

- 6

Drive attempts to
eject disk but doesn’t

Floppy Drive

1 Push disk completely in.
2 Remove top cover and attempt to eject the disk.
3 Eject disk manually.
4 Replace floppy drive.

(Continued)

Troubleshooting Symptom Charts/Hard Drive - 7

Hard Drive

Internal hard drive
runs continuously

Internal hard drive
will not operate

1 Replace hard drive data cable.
2 Replace internal hard drive.
3 Replace logic board. Retain customer’s SIMMs.

1 Replace hard drive data cable.
2 Replace hard drive power cable.
3 Replace hard drive.
4 Replace logic board. Retain customer’s SIMMs.