In my previous articles on floppy drives, "Start with the usual suspects when diagnosing floppy-disk problems" and "Beware of the CMOS and loose cables when fixing a floppy drive," I outlined some common floppy-disk-drive-related problems and fixes. However, once you’ve verified that a problem isn't caused by a corrupt disk, an OS conflict, or a loose cable, you need to determine whether the problem lies with the floppy drive itself or the disk controller. Here are a few ways to help you determine the cause of the problem and some possible fixes. I'll also discuss the issue of repairing vs. replacing a dead drive.
Try a known-good floppy drive
To determine whether your problem involves the disk drive or the disk controller, locate another PC whose floppy drive works properly. Unplug both PCs, open the cases, and switch floppy drives and the data cables attached to the drives. Then, put the machines back together, power up the machines, and test them.
Scenario A: The controller's bad
If the machine that was originally having the problems is still having problems, the problem lies with the disk controller. Unfortunately, there are no serviceable parts on a disk controller. Just make sure the CMOS settings are correct. If they are, you’ll need to replace the disk controller.
Most often, this requires replacing the system board. However, I have been able to find PCI cards or ISA cards with disk controllers built into them. If you’re lucky enough to get your hands on such a card, disable your onboard disk controller (usually through the CMOS, but possibly with a jumper), and connect the floppy drive to the new disk controller.
Scenario B: The drive's bad, the cable's bad, or the cable's loose
If the computer that was having the problem is now working correctly, test the computer that was known to be functional to see if its floppy drive is working. If its floppy drive also works, you probably just had a loose cable; if it's not, the problem is either the drive itself or the data cable. To find out which component is at fault, move the data cables back to the machines they originally came out of so that each computer uses its original disk controller and data cables, but the floppy drive from the other computer.
Test both systems again. If the problem moves back to the computer that was originally having the problem, the cable is bad and needs to be replaced. You can get floppy drive data cables from any computer store for just a few dollars. If on the other hand, the known-good computer's drive now doesn't work, and the computer whose drive was broken now has a working drive, the problem lies with the floppy drive itself.
Put the good floppy drive back into the known-good computer and return the computer to its original location. You now have a decision to make. You must decide whether to repair or replace the floppy drive.
Replace vs. repair: It comes down to time
Since it’s common to find floppy disk drives for less than 20 dollars—quite amazing for a component that cost hundreds of dollars just a few years back—price usually isn't a factor in the decision to replace or repair a floppy drive. In my experience, the biggest consideration in deciding whether to repair or replace a drive is time. It may be faster to repair the drive than to drive all the way to the store and buy a new one.
In my next article, I’ll share several techniques for repairing a malfunctioning floppy disk drive. As the vast majority of problems are related to the drive heads, the techniques I discuss will focus on them. However, these techniques won’t work if the drive has a dead motor, cracked circuit board, or some other electronic malfunction. If you suspect the problem is as severe as these, it’s best to go ahead and replace the drive.
Should the floppy go the way of the Dodo?
Is it time to retire the venerable floppy drive? With the proliferation of CDs, CD-Rs, CD-RWs, Zip drives, SuperDisks, and recordable DVDs, is the 3.5-inch floppy obsolete? Post a comment to our ongoing discussion about the floppy's future.