1541 won't read disks and won't format disks

bradhig · April 7, 2016

When I try to read a disk or format one the drive knocks ,the red light flashes , and it says file not found on the screen. I have another 1541 but the motor won't stop spinning when I start it up. My 1571 is starting to fail. It sometimes does't read the directory off disks.

7800fan · April 8, 2016

First drive, it almost sound like it's trying to read a blank disk. Is the disk formatted for Commodore use? If not, it will make noise then return error. IBM, Apple II, and other formats are not compatible or readable in any of 1541s.

Second one: is the drive activity light flashing a sequence? It could be a chip onboard had failed the power on test.

1571 could be just dirty head. 5.25" disk cleaning used to be common in many stores back in the day but it's hard to find one today for a price that doesn't make you crap in your pants. I'm lucky I still have a $10 disk cleaning kit from Kmart that still have uses left.

bradhig · April 8, 2016

First drive won't read any commodore 64 disks period. Second drive doesn't flash any light sequence. Motor just runs. Green light comes up.

carlsson · April 8, 2016

Second drive, measure the voltages from the power supply so you've got both 5V for the logic and 12V for the motor. If the 5V is missing, the motor will keep spinning because no logic tells it to stop. There are other faults that can cause this too.

Yet again, try Ray Carlsen's articles as they tend to be the gospel (?) when it comes to troubleshooting Commodore gear:

http://personalpages.tds.net/~rcarlsen/cbm/1541/1541chip.txt

http://personalpages.tds.net/~rcarlsen/cbm/1571/1571diag.txt