I have a 70-200L F2.8 USM lens. It is very sharp, clean and 6 years old. Nowadays, AF does not working properly, in low light, it does not focus. I tested other lenses (100mm and 100-400) in the same circumstances and they are working normal. AF works only outside but it is too slow. I guess US motor needs to be replaced but I am not sure what may cause this problem. I called Canon Customer Service but they did not give an estimate. if somebody knows what may cause this problem and how much Canon service charges, I will appreciate. Based on estimate, I will keep it or sell in this condition.
I can't begin to tell you what's wrong, but Canon repairs are generally based on a flat rate to open, inspect, and close the lens, plus any parts needed. Most repairs I've had on 70-200 f2.8s have been around $220-$290. YMMV of course (and yeah, I have a lot of repairs :-)
I think you can send the lens in, and if you don't approve the estimate, they'll ship it back for free. Might be wrong, but I seem to think the shipping back is free.
Lately they seem to have a flat rate for simple repairs and adjustments. I agree with Rocketball... it's about $170-$175 including overnight shipping back to you. Good luck! I know others have had problems with service, but they've been great when I've needed them.
