C64 Dead Test, Diagnostic & Troubleshooting

In case it’s not obvious, the purpose of this (and the originals) is to provide instructions to help diagnose problems with a Commodore 64. Any owner of a Commodore 64 should be prepared to be faced with a non-working computer, and that applies to new builds (like a SixtyClone self-build) as much as an original machine. Therefore an essential part of your armoury should be both a Dead Test and Diagnostic cartridge. These days such cartridges are available from numerous sellers and are usually “all in one”, requiring a simple jumper change to be either a Dead Test or a Diagnostic cartridge. To undertake a complete diagnostic test a loopback harness is required which plugs into the keyboard connector, user port, cartridge port and joystick ports allowing signals to be tested. There are a few options when it comes to acquiring a harness and sellers can be found with a simple Google search. This manual gives instructions in how to use the Dead Test and Diagnostic software and provides further troubleshooting information to dig deeper into issues you may be experiencing.