T3i not able to communicate with lens

[romlein]

My several-years-old T3i is unable to communicate with any lens I attatch to it. This problem started, then went away a week or so later, and now a week later is back. Lens won't autofocus, and aperture box reads "00" and can't be changed.

I've tried:

• Firmware (up to date)
• Resetting to factory defaults
• Cleaning both lens and body contacts with alcohol and swab, and
• (against a few recommendations) the rubber eraser trick.

No luck.

[jrhoffman75]

Do you have access to a second lens? Could be camera or ribbon cable inside lens. Need to have a diffeent camera or lens to test which is malfunctioning.

[romlein]

Hi John,
Yeah I've tested it with three lenses now, so I'm fairly confident the problem is with the body.

[ebiggs1]

You ned Canon service as your T3i is faulty.  Maybe a good time to upgrade?

[TTMartin]

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@romlein wrote:

• (against [Canon's] recommendation) the rubber eraser [mistake].

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Canon EOS Error Messages: An explanation and understanding

'Warning: do not clean lens contacts on either a Canon lens or the camera body with an eraser! It’s incredibly easy to rub off the gold plating on these contacts, and end up with data communication problems, even if that wasn’t the original source of the problem! It’s obviously a good idea to clean the contacts if a lens communication error is reported, but our strong recommendation is to use a soft, clean cloth, perhaps moistened with isopropyl alcohol if you feel the contacts are smudged with fingerprint oil or similar debris and really need a cleaning agent. Again, do not use anything abrasive, and to repeat: do not use an eraser!' ~ Canon

[ebiggs1]

" It’s obviously a good idea to clean the contacts if a lens communication error is reported, ..."

I can't remember this ever working.  Maybe it does but I have not seen it.