Canon TS8251 - intermittent 5011 error

[Glomgold]

I got a 5011 error out of the blue. The error appears a few seconds after I power it on, the carriage doesn't move, sometimes it tries to move right before the error appears.

I have had it running normally 2-3 times, when it starts up normally it's nothing wrong, no strange sounds.

There was quite a bit of ink in the area around the pads, I've cleaned this up.

The encoder (?) strip is clean as far as I can see.

I cleaned a metal plate facing forwards, the carriage moves along the plate, it was full of ink.

No paper jams.

Nothing loose that I can see or hear when I tilt the printer to all sides.

I've had it disconnected from power for days etc.

I'm planning to remove some panels to get a better look at things, but I really don't know what I'm supposed to look for.

 

[PeterBJ]

There are no service manuals available for the TS8251, but service manuals for other AIO printers suggest a scanner error.

Druckerchannel.de has an article with lists of Canon error codes here. You can use Google translate or other translator if you don't read German.

Here is a clip translated to English:

 

[Glomgold]

Thank you.

The scanner moves ever so slightly when I turn it on. It's been standing in one place since new, I'll try an disconnect it.

 

[Glomgold]

I've disassembled it as much as I dared, cleaned the encoder strip, reseated some ribbon cables. No change, it could be the scanner.

The scanner only moves ever so slightly, about a centimeter, the error appears when it has gone back. I don't see anything that's broken.

 

[The Hat]

The scanner only moves ever so slightly, about a centimeter,

Did you remove the packing screws to free up the scanner..

 

[Glomgold]

Did you remove the packing screws to free up the scanner..

I'm not sure I understand. The scanner has worked before, I don't recall removing any screws.

 

[PeterBJ]

I have a TS8351a, which i think is very similar if not identical to the TS8251a. It has got no scanner lock or locking screws.

 

[Glomgold]

Extremely annoying to have to throw out a printer for this kind of error. The error code is so generic, could be a hardware problem too.

 

[Garretwilliam]

That 5011 error on Canon printers is usually carriage/position sensor related.
Since it sometimes starts fine, I’d suspect either:
encoder strip still slightly dirty or misread carriage binding from ink build-up on the rail
or a failing carriage sensor / timing issue
If cleaning didn’t fix it, opening it up won’t help much unless you can spot friction or misalignment on the carriage movement.

 

[Glomgold]

The carriage moves freely, I don't see anything obvious wrong. At this point it's not important that I will be able to put it together again, should I try to remove the whole carriage and clean it on the backside?