Sad Mac Error Codes

UPDATE!

Gary Rice generously released the Black & Bleu - The Ultimate Mac Error Codes Utility on Macintosh Garden. This is an excellent resource for making sense of the Sad Mac codes, more than what is listed below.

Apple's overview below is a good guide to introducing yourself and getting basic ideas about the Sad Mac codes. Then, the Black & Bleu program for 68k and PPC Macs running System 7.0.1 through 9.2.2, as well as OS X 10.2, can provide a more detailed list and details of the Sad Mac codes as well as the error codes on vintage Macintosh computers.

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Retrieved from support.apple.com on August 3, 2022.

I applied minor grammar and spelling corrections. The original printout has been attached herein as a PDF file.

This article has been preserved here on Tinker Different in case the original Internet link breaks, as this is more comprehensive than other Sad Mac Errors posted on the Internet some years back. There are paper copies of a much more comprehensive list of Sad Mac error codes somewhere.

If you find one, please let me @retr01 know. Thank you.

Macintosh: "Sad Macintosh" Error Code Meaning​

This article lists and explains the error codes accompanying the "sad Macintosh" icon on the screen when a Macintosh computer does not start up.

This article has been archived and is no longer updated by Apple.



Products Affected

The "sad Macintosh" icon and its associated error codes exist only in older Macintosh computers. Newer models, such as those with Universal Serial Bus (USB) or Open Firmware, use different mechanisms to report such failures. For more information on newer systems, please see the following articles:

Article 58183: "Power-On Self-Test Beep Definition - Part 1"
Article 58442: "Power-On Self-Test Beep Definition - Part 2"
Article 95036: "Power Mac G4: Power-On Self Test"


Overview

The particular error code with the "sad Macintosh" is not as important as when it occurs. If the Macintosh can start up from a different system disk, the fault is probably with the system software on the other disk. System faults are usually identified when you get a "happy Macintosh" face and the "Welcome to Macintosh" screen before the "sad Macintosh." Suppose the "sad Macintosh" appears immediately when you turn on the computer usually suggests an issue with the logic board or memory. Try starting from a floppy disk before assuming it is a hardware fault.


Sad Mac Error Codes Description

On the Original ROMs (Macintosh 128K 512kK 512kK, Plus):

When you press the interrupt button on the side of your Macintosh when starting up, a sad Mac icon on the screen with '0F000D' and some bits cycling under the icon indicate it is performing a memory test.

This numeric code is in two parts:

• The first two characters are the class code. The class code tells what part of the diagnostic program found the error.
• The second four are the subcode. The sub-class code tells what the error was. In the case of a bad RAM chip, the sub-class identifies the bad chip (this was very helpful to homegrown upgraders).

Macintosh SE and Macintosh II ROMs

The "sad Macintosh" error codes for Macintosh SE and Macintosh II computers were changed to incorporate additional testing power and support the 32-bit world. Generally, 68000 exceptions are the same codes as the Macintosh but are displayed differently.

Traditional

The traditional Macintosh error codes are displayed in hexadecimal notation like this: 0F0003
Where F indicates an exception and three indicates an illegal instruction occurred. On the Macintosh SE and Macintosh II, the display would appear:

0000000F
00000003

Power On

The power-on error codes have the following format:

XXXXYYYY
ZZZZZZZZ

Where XXXX is internal test manager state information (ignore this), YYYY contains codes that indicate either an exception code or the test number for power on test failure. The ZZZZZZZZ code contains additional failure information to help track down the fault.



Macintosh Portable ROMs

The startup code in the Macintosh Portable contains a series of startup tests to ensure that the fundamental operations of the computer are working correctly. A "sad Macintosh" icon with code describing the failure appears on the screen. Here is a typical example of a Sad Mac display with an error code below it:

SAD MAC CODE

05460203 = (D7.L)
000OB6DB = (D6.L)

The two codes are the contents of the two CPU data registers, D6 and D7. The upper word (upper four hexadecimal digits, in this case, 0546) of D7 contains various flags used by the startup test routines. It is unimportant to everyone except a few test engineers within Apple. The lower word of D7 is the major error code. The major error code identifies the general area the test routines were in when a failure occurred. D6 is a minor error and usually contains additional information about the failure, like a failed bit mask.

SAD MAC CODE BROKEN DOWN

Test Flags Major Error
0546 0203

Minor Error Minor Error
0000 B6DB

Herein, the major error is broken into the upper byte that contains the number of any 68000 exceptions that occurred ($00, meaning that no exception occurred) and the lower byte that usually has the test run at the time of failure. If an unexpected exception occurred during a particular test, then the exception number is logically ORed into the major error code. This way, both the exception that occurred as well as the test that was running decoded from the major error code:

SAD MAC CODE FURTHER BROKEN DOWN

68000 Exception Test Code
02 03

In this example, the code says that an address error exception ($0200) occurred during the RAM test for Bank A ($03); $0200 ORed with $03 = $0203.

Major Error Codes

Below is a brief description of the various test codes that might appear in the major error code:

Important: Some of these codes may mean slightly different things in Macintosh models other than the Macintosh Portable. These descriptions describe the error codes in the Macintosh Portable.


Minor Error Codes; Power Manager Processor Failures
Suppose a communication breakdown occurs during communication with the Power Manager. In that case, the following error codes appear somewhere in the minor error code (usually in the lower half of the code, but not always):


Diagnostic Code Summary
Below is a summarized version of the Sad Mac error codes:




Published Date: Feb 18, 2012