Canon GP160DF Service Handbook page 175

##0795 [TX/RX] Problem occurred in the ?communications? decoding processing
Cause
• The communication codec is busy.
##0799 [TX] System error
Cause
• EOR output attempted during speed dial
procedure.
CHAPTER 5 SELF DIAGNOSIS
Countermeasure
(1) Turn the power off then on.
(2) Replace the FAX PCB.
Countermeasure
(1) Turn the power off then on.
(2) Replace the FAX PCB.
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