Canon 135L AF Problem

I just received my 135L in the mail today. I bought it new from Amazon.
The problem is that whenever I try to autofocus, it flits back and forth continuously, never actually settling on a focus point. It will stop for half a second, then change its mind and switch to one farther away, then go back to the original one, and then back again to the other one, back and forth back and forth.
I've tried all three AF modes, the problem still persists. MF works fine.

Help? WIll I have to send it back to Canon?

I'm nervous about this because I'm leaving for Europe this weekend and want to take this lens with me

how is the battery charge on the camera? also, look on the side of the lens and double check to see which position of the "distance switch" (I have no idea what it's called) is set at the appropriate.

Full battery, and I've tried it at both 0.9 and 1.6.

hmmmmm.... and the camera's AF works well for other lenses too? I assume this is true..

Just to be clear, you arent sitting in a dark room with the curtains pulled are you?

BFox549 wrote in post #15983615
hmmmmm.... and the camera's AF works well for other lenses too? I assume this is true..

Yep, it works perfectly fine with my other lenses.

gonzogolf wrote in post #15983615
Just to be clear, you arent sitting in a dark room with the curtains pulled are you?

Nope.

burninghotcheese wrote in post #15983619
Yep, it works perfectly fine with my other lenses.

Nope.

Sorry had to ask, sometimes people amaze me. My copy of this lens is quick and accurate in obtaining focus. Might be time to send it back.

And you dont try to focus on a subject which is closer than 0.9m to your sensor?

Just asking because like above said, people sometimes

Try it on someone else's camera. Or send it back to Amazon. Do not let your return window lapse.

Make sure your focus limiter is not set incorrectly and trying to AF on something too close.

If still no AF on something far away, exchange it.