Affected models: Canon imageCLASS, FAXPHONE, PIXMA and MAXIFY models with fax, and imageRUNNER office machines. It appears as #018 in the job log or on a transmission report.
What This Error Means
When a fax doesn't connect, your Canon doesn't give up on the first try — it waits and redials automatically, usually a couple of times. Code 018 is what it logs when those retries are exhausted and it still couldn't get through.
This matters, because it tells you the failure is persistent rather than a one-off. Canon's manuals describe 018 as the line being busy or disconnected, and the report label pairs those two together: either something answered with a busy tone, or nothing was there at all.
How this differs from code 005: with 005, the other machine simply didn't answer within 35 seconds on the attempt. With 018, your printer has already retried and the line is still unavailable. Same family of problem, further along.
What Causes It
- The recipient's line is genuinely busy — common with small offices running one phone line for voice and fax, or where another fax is already arriving.
- Their machine is switched off or unplugged from the phone line — nothing answers, so your printer reads "no signal".
- Your own line has no dial tone — the "disconnected" half of the code. If your printer can't get a dial tone in the first place, every fax fails this way regardless of who you're sending to.
- An international number sent without a pause — Canon's documentation attaches this specifically to 018. Without a pause after the international access code, the connection doesn't have time to establish.
- Dialling out through a switchboard without a pause — same mechanism when your office needs a 9 or a 0 to reach an outside line.
- The number is a voice line — a person answering, or an answering machine, doesn't produce the fax tone your printer is waiting for.
How to Fix It
Fix 1: Check your own line has a dial tone
- Unplug the phone cord from the back of the printer.
- Plug it into an ordinary telephone handset.
- Listen.
Silence means the fault is your line, not the recipient — and no amount of resending will help until your phone provider fixes it. A normal dial tone rules this out and points you at the recipient's end.
Fix 2: Ring the fax number yourself
Dial it from a phone. A continuous busy tone means their line really is occupied. Harsh electronic screeching means their fax is answering fine and the problem is timing. A person, a voicemail greeting, or ringing out tells you the number is wrong or their machine is off.
Fix 3: Resend at a quieter time
If the line was busy, that's the whole story — wait and try again. Early morning tends to work better than mid-afternoon. Retrying immediately achieves little, since your printer already did that for you.
Fix 4: Add a pause to international or switchboard numbers
- Enter the number as usual.
- After the international access code, or after the 9 that gets you an outside line, press the Redial/Pause button.
- A
p or a comma appears in the display. Two is a sensible starting point. - Enter the rest of the number and send.
If you've faxed this number successfully in the past without pauses, skip this — something else changed.
Fix 5: Check the phone cord is in the LINE socket
Only relevant if this printer has never sent a fax successfully. Canon printers have two similar sockets: the cord from your wall jack goes in the one marked LINE, while EXT is for connecting a handset to the printer. Reversed, you get exactly this symptom. Unplug the power before moving cords.
If None of That Works
If your line has a dial tone, the recipient's fax answers when you ring it, and 018 still comes back on every attempt, the likely culprit is the line quality between you — particularly if your phone service runs over cable or internet rather than a traditional copper line. Fax tones don't survive digital compression well. Your phone provider is a better first call than Canon here.
When you do contact Canon, have ready: your model number, the serial number from the sticker on the back or underside, the exact code (#018), whether the same thing happens to more than one number, and whether your phone service is a traditional landline or internet-based.
