Error Codes and Self Diagnostics are designed to help the technician discover what the problem is without having to inspect the machine. They are very accurate for the most part but can lead you in the wrong direction sometimes. For the customer and the Do-It-Yourselfer finding what the error code actually means can be the problem. I can help the Do-It -Yourselfer with the error codes on many differant makes and models. If you would like to have your own service manual and parts guide I recomend This website. Let me know if you need my help by posting a comment.
Be sure to leave the make and model of your machine and also the error code and any other information that may be important.
Example of self-Diagnostic error code.
Hewlett Packard error code 50.1
This means there is a problem with the fuser assembly