35L slow focus speed needs repair, cost?

bought a 35L a few months ago on here. lens is sharp and it takes great pictures, but having now read about how fast the lens should be, mine is clearly malfunctioned (for the record, i just assumed the lens focused that slow. it's been focusing at the same speed since i purchased it, not something that recently occurred). thanks a lot LennyDoolan

regardless, i'm the one that needs to fix it. it's my own fault for not realizing sooner how fast it should be. has anyone done this repair before? i'm taking it to canon in irvine, ca in a few weeks, but was just wondering if any of you could shed some light on what kind of repair fees i might see.

i should note that i went into a store, tested a new 35L, and the focus speed was significantly faster than my own

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