Canon MP830 - PIXMA Color Inkjet Service Manual page 19

2-7. Fax Communication Troubleshooting
(1) Identification of a trouble
A fax machine transmits image data to a receiver through a telephone line. A trouble in any of the transmitter, receiver, and telephone line can
prevent the machine from transmitting image data properly.
For the best solution to your fax trouble, follow the flowchart below to determine whether it is a communication trouble or not.
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