EF-S 17-85mm f/4-5.6 IS USM Focus moves erratically but can't lock in

[timtom64]

Hello all.  Suddenly, whenever put into auto-focus mode, this zoom seems to go a bit crazy as it erratically attempts to focus on something, but it cannot.  It just keeps moving erratically but never finds a home.  Does anyone have trouble-shooting suggestions?  Thank in advance!

[normadel]

There are numerous things that can account for trouble autofocusing. Some are:

1. How the focus area is set.If multiple focus points are being used and the field has near and far subjects;

2. If the subject being focused on lacks any texture, contrast or is too dark. There can be big differences between indoor and outdoor scenes in this regard.

3. Your subjects indoors are too close for the lens you are using. All lenses have a minimum focus distance.

Is your indoor lighting bright or dim? This can be widely variable. The camera doesn't know whether it is indoors or outdoors. It knows light brightness and subject focusability. 

[timtom64]

The issue persists whether I shoot inside or out.  All my other lenses work great.  I have since purchased an R6 so I think I'm just going to give up on this lens since I now have another lens that covers the same range.  But if anyone pops in with a possible solution, I'm all ears.  Thank you, everyone.

[timtom64]

Sorry for the confusion, all.  I'm reading through this thread and realize I must have posted a solution to a problem I had with another camera that got wet.  Which also means I must not have posted it to the right thread.  Uggg.