Fixing a Macintosh Computer

By Bob O'Lary
bob@bitbrothers.com

 

Macs are simple in their operation, but have several variables that can cause problems when trying to find a bug. The simplest way to troubleshoot any Mac related problem is to remove all variables, then systematically check each system component till the error or "bug" is discovered.

Though Macs are all made in a similar manner, with like kind components, the software that runs it can be written from several different vendors (who may or may NOT follow Apple's development rules), and this is the source for the majority of conflicts that confuse the Mac operating system.

The first step in fixing an errant Mac, is to determine whether it is a hardware or software related problem. You will need an external bootable source to work on virtually any Macintosh, so gather tools of the trade, ie: Bootable floppy disk, CD Rom with YOUR MAC'S System folder on it, external Hard drive, or Jaz or Zip Drive with a universal Mac system on it.

Remember, you can NOT repair or alter a system folder that is being used by a running Macintosh, thus, you must start the Mac from an external/alternate source than the computer's internal hard drive. Doing this will enable you to quickly determine if the problem is hardware, or software related. If the machine boots up nicely with an external source, odds are the Mac's problem is related to the software that is on its internal hard drive. (This assumes the internal hard drive is not frozen up, or not spinning for another reason). Usually, if it can spin, it can be fixed.

Another good tool to own is a disk repair utility like Norton Utilities, and the system CD-rom that came with that model Mac. Each model of Macintosh has its own specific system folder requirements, and if these control panels and extensions are not present, the Mac will not properly boot up.

Lastly, common sense (putting on your Sherlock Holmes cap) goes a long way in logically deducing what the problem could be. Understanding how the Mac works is our best clue for tracking down and repairing any Mac malady!


Step#1 Isolate all variables

(remove all peripherals, boot from external source)

 

Step#2 Think what has recently been changed

(Has new or different software recently been installed)

 

Step#3 Systematically check each component

(starting at the keyboard, check ALL cabling for firm connections, then move on to software system and applications that launch during start-up)

 

You're WELL on your way!!


Mac OS Boot-Key Combinations & Other Key Combos

(special thanks to Brenda Fraser of Ft. Braden School)

 

 

Start Up Keys

Press the following key(s) Combos on startup to achieve the desired command.

 

Command Key Sequence

Rebuild desktop command+option

Zap PRAM at startup command+option+p+r

Open extensions manager

at startup space bar

Boot from cd-rom at

startup c

Disable extensions shift key

Start without finder

windows open option

Disable startup items

only shift (before loading extensions)

Boot with Virtual Memory

off command

Boot from a particular command+option+shift+delete+(scsi

scsi id number ID number)

Reset video at startup command+option+o+v

Eject floppy at startup [mouse button]

Prevent booting from

internal HD command+option+shift+delete

Force Quadra AV machines

to use TV as a monitor command+option+t+v

Force PowerBooks to reset

the screen r

Rebuild floppy desktop command+option + insert floppy

Force interrupt

application command+[power key]

 

Other Useful Key Combos

 

Command Key Sequence

Force application to quit command+option+esc

Bring up dialogue for

shutdown/sleep/restart power key

Fast shut down control+option+command+power key

Unconditionally reboot control+command+[power key]

Force restart control+command+[power key]

Force restart on iMacs shift+command+[power key]

Eject floppy command+shift+1

Screen grab (as Picture

1) command+shift+3

Screen grab (7.6+) for a

specific area command+shift+4

Apple System Installer:

Change custom install to command+shift+k

clean install

 

Close all open windows option + starting/quitting

application

Select (highlight) all

items in an active window command+a

Copy selected item to

Clipboard command+c

Paste item from the

Clipboard (applications command+v

only)

Undo last edit command+z

Print file (application

only) command+p

Cancel print or copy job command+[period key]

Quit (application) command+q

 

Finder Key Combos

 

Create a new folder command+n

 

Open a File or Folder command+0 (zero) or command+[down

arrow]

Open a highlighted command+o (letter) or command+[down

icon arrow]

Select the next

alphabetical icon tab

Select the previous

alphabetical icon shift+tab

Select an icon to the

left left arrow (in icon view only)

Select an icon to the

right right arrow (In icon view only

Select an icon above up arrow

Select an icon below down arrow

Duplicate a selected

item command+d

Close an active window command+w

option key+"close" from the File menu

Close all open windows option key+clicking any window's close

box

option+command+w

Erase Floppy Disk command+option+tab+inserting disk

Get Info command+i

Find file command+f


 

Useful WEB Sites for Mac Repairpersons

 

 

Apple Computer's Technology Information Library (TIL):

http:// til.info.apple.com/

 

The MacResource Page:

http://www.macresource.pair.com/

 

Cheap RAM Prices:

http://www.ramjet.com/

 

MacCentral, The #1 Source for Mac News on the WEB:

http://www.maccentral.com/

 

Mac Software Version Tracker:

http://www.versiontracker.com/

 

MacAssistant.Com's Online tutorials:

http://www.macassistant.com/tutor.html

 

Giant, comprehensive collection of All-things-Mac Links:

http://www.siamweb.org/technical/Mac-L/links.html