Recently I was asked for advice on how to troubleshoot a Color Classic that won’t power on.

There are a lot of great troubleshooting resources across the internet that address this topic with helpful advice. This post isn’t meant to replace them but simply to consolidate the recommendations I’ve found helpful in the past. Hopefully it will help you get your CC up and running!

1. First verify you are using a known good power outlet and cable. Remove any surge protectors or power strips as well as any external peripherals from the CC like attached hard drives, printers, or modems.

2. Be certain the power switch on the back of the computer is in the ON position (top part is pressed in). Make sure the keyboard is attached and firmly press the power button on the keyboard.

3. Reset PRAM (hold down command-option-P-R while pressing the power button, continue holding these keys down until the computer chimes at least 3 times, then release).

4. Unplug the power cable from the CC. Remove the logic board by taking out the two retaining screws on the back panel, then pressing on the tab at the top and pulling the panel out. Grasp the logic board firmly on each side and pull out directly.

a. Use canned air to blow dust accumulation from the logic board if necessary. Avoid the temptation to vacuum it since the static electricity can ruin the logic board.
b. Clean the contacts at the front edge with a cotton swab moistened with isopropyl alcohol.
c. Clean the socket inside the CC the logic board slides into with a cotton swab moistened with isopropyl  alcohol.
d. Remove the memory SIMMs (and if present, the VRAM) and clean the contacts with a cotton swab moistened with isopropyl  alcohol. Carefully reinsert them and be certain they snap securely into their upright position.
e. Press the CUDA switch briefly on the logic board (the tiny button near the ADB ports) and release.
f. Reseat the logic board by sliding it in and making sure it snaps securely into place. Remove and reinsert it a few times to help insure a clean connection.

Plug in the CC and see if it starts up.

5. If the CC still won’t start up unplug the power cord, remove the logic board and take out the 3V.6 battery on the logic board. Reinsert the logic board, reattach the power cable, and try again.
6. Sometimes the CC needs at least 24 hours with power attached and the switch on the back in the ON position before it will revive.

Still no joy? Remove the logic board and inspect it for traces of leakage around the capacitors (dark areas). If you see evidence of leakage if may be shorting the trace connections on the logic board. Believe it or not, a trip through the dishwasher is recommended for this. I won’t be the one to guide you down that road, though, I’ll leave it to those who have done it. See these great forums for assistance:

Good luck and feel free to post comments and results below with your experiences troubleshooting the Color Classic.

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3 Color Classics - front

3 Color Classics - front

My wife is thrilled when I turn the dining room table into a computer repair workshop. As you can see from the photos above the patients for this day included two Macintosh Color Classics that refused to start up. The Color Classic web server was temporarily taken offline to serve as my “known working” device to test parts from the other two.

One of the two nonworking CC’s was purchased for a song from ebay with a known faulty logic board but everything else was promised to be fine. This proved to be true – installing an LC575 logic board into it produced a healthy startup chime and a clear bright screen when booted from the internal hard drive . Since the system file on the HDD hasn’t been hacked it produced a bus error when trying to load the Finder, but that appears to be a software issue rather than a hardware one.

3 Color Classics - reverse

3 Color Classics - reverse

The second CC is one that previously worked fine and even has a rare Sonnet Presto Plus accelerator card installed. After sliding out the logic board and removing the accelerator card I could see very evident traces of leaking capacitors. I’ve located a working replacement logic board but it’s just a matter of time before it also succumbs to the ravages of time and suffers the same fate, so I guess I will need to brush up on my soldering skills.

Color Classic logic board and Sonnet Presto Plus

Sonnet Presto Plus accelerator and Color Classic logic board

The Color Classic web server is back online and I am still working on getting a spare backup ready to go to pinch hit in case of hardware failure. It is, after all, 17 years old. Back in 1993, when the Color Classic was released, Apple’s annual sales amounted to just under $8B, virtually all of it from sales of 3.3M Macs. In 2009 Apple’s annual sales were $36.5B, from 10.4M Macs, 54M iPods, and 20M iPhones.

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I’ve had a pair of Macintosh Classic II computers awaiting diagnosis and repair for over a year now. Both suffer from the same issue – a checkerboard pattern on the screen that appears on startup and remains. After perusing the helpful forums over at the 68k Macintosh Liberation Army I determined the issue is almost certainly leaking capacitors.

Not long ago I was able to purchase a replacement Classic II logic board for a few dollars on ebay as an unused Apple Service part. I was thrilled that I might get at least one of the Classic II Macs back to health without having to remove and replace a bunch of capacitors with a soldering iron.

Above is a photo of the new and the old logic boards. It’s pretty easy to tell which is which. Sadly, though, the new logic board is not without problems. Although the Classic II now starts up properly there is no sound. I’ve reseated RAM and ROM modules without any change. Another tour through the 68KMLA forums reveals this is a common symptom of, you guessed it – leaking capacitors.

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My thifty ebay Mac SE purchased arrived recently and I finally found time to unpack it and power it up. I knew from the original auction description that it had an issue of booting to a flashing question mark. I figured that in the best case scenario I’d just have to reinstall the System software on it.

I wasn’t that lucky, unfortunately. When I power it on it sounds like the internal HD is stuck in a constant effort to read the drive and not finding any success. I will post a sound file so you can hear it. After reading the troubleshooting information at Chris Adams’ SE Support pages it fits the description of  drive “stiction” – a term I remember knowing many years ago.

The good news, however, is that the floppy drive works fine and I was able to boot the machine from an old 800k Norton Utilities Emergency Disk and from an older Apple Disk Tools floppy. Neither HDSC Setup, Disk First Aid, or Norton Disk Doctor were able to see or mount the internal HD, although the drive activity indicator on the front of the SE flashes.

So it looks like step 1 will be to replace the internal SCSI hard drive. Step 2 is going to be upgrading the RAM. I have not yet confirmed, but suspect that the RAM is only 1 MB since when I tried to boot from a System 7.5 Disk Tools floppy I got a dialog box that simply said “System 7.5 needs more memory” with no other option but to shut down.

I consulted the Adding RAM section of Chris’ SE Support site and after skimming the instructions discovered that it’s not just a matter of replacing four 256MB SIMMs with four 1 MB modules in the RAM slots. You also have to clip a resistor so that computer knows about the change in memory configuration.  That should make things more interesting!

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Mac SE SuperDrive

Mac SE SuperDrive

My very first Macintosh was a Mac SE, purchased in December of 1988 from the University of Texas Student Computer Store. Even with my student discount I had to take out a loan from the University Federal Credit Union to pay for it. My SE came with two internal 800K floppy drives, no internal hard disk and one MB of RAM (later upgraded to 4 MB). My accessories included a Jasmine 20 MB external hard disk, an ImageWriter II printer, and a Practical Peripherals 2400 baud modem.

Recently I purchased a Mac SE to add to the ClassicMacs collection. This one is slightly newer, since it has a SuperDrive (a floppy drive that will read/write high density floppy disks and an internal hard disk).

When I reviewed the price list for the SE models available when I bought mine I quickly remembered why I bought the one with two 800k drives – the one with an internal 20 MB hard disk was priced $800 higher!

As I recall the external Jasmine 20 MB drive was $400, so I saved $400 by going that route. My Mac came with an early version of System 6 and would have to wait until May, 1991 before System 7 was released.

I’ll keep you updated on the addition of the Mac SE to the classicmacs.org collection. I think it will be a System 6 machine to remind me of how I started out.

Helpful Mac SE Pages

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