Canon ImageClass D660 internal blinking l.e.d.

Oct 27, 2014 3 Replies

This Canon ImageClass D660 printer/scanner/fax was subjected to a power surge. An open neutral line on the customer's street knocked out a lot of equipment in a lot of homes. I was able to locate the damaged power supply board by following the fine aroma of charred components. The result of the damage was that it just needed a few capacitors and a T4A fuse. I powered it back up and was able to print a test page ok. However, before I proceed putting this all back together to check everything else, I noticed that there's an l.e.d. on the system control(?) board which has an amber l.e.d. that continuously blinks like a turn signal.

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Does anyone know if this is normal?



Thanks for your reply.


David Farber Los Osos, CA

It's probably a watchdog circuit. Used to indicate proper operation. If it stops blinking, it means the processor is locked up. Perfectly normal.

Thanks for that explanation. Everything seems to be working fine. I'll reassemble it and stop worrying about it. :-)

David Farber Los Osos, CA

I never expected to see a blinking LED inside (nothing seen of them on the outside) an audio amp. Suspecting it may sometimes be possible to end up with a clicking sound coming over the audio, via shared ground routes or whatever - but there are such blinking LEDs in normal operation

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