Using 100mm/2.8 USM on older EOS Body no AF

[AnselAdams4x5]

I just purchased a 100mm/2.8 USM Macro lens. Works perfectly on my 6D. It does not respond at all on my film EOS A2. I have three other EF lenses, 17-40 L, 28-135 IS and 70-300 IS. All of these other lenses work fine with my film EOS A2. Does anybody know why?

[ebiggs1 · Accepted solution]

" Have you tried cleaning the contacts on the body and the lens with rubbing alcohol."

Unlikely to help since the other lenses work just fine. Cleaning the contacts rarely to never helps if the lenses are routinely changed. That act is generally enough to keep the gold plated contacts in order.

[deebatman316]

That camera uses 2CR5 batteries. Not the typical rechargeable batteries we have today.

[ebiggs1]

Not the point, my  friend, the battery(s) may be under capacity.  Quote, "If it is still the original replace it today."

[deebatman316]

But why would the other lenses work fine then.

[AnselAdams4x5]

Battery indicator shows good and all my zooms work fine on old A2