Why did my power adapter die?

I’ve got a 85W Magsafe 2 power adapter (Model A1424). The other day it just suddenly stopped charging. No LED on the tip, and no charge indicator on my MBP. I cracked it open, because I’ve got nothing to lose and $100 to potentially save.(discharged caps of course) I’m hoping for something simple like a blown fuse or something, but I didn’t see any skid marks or obvious failures on first inspection. The components are packed pretty tightly, and there’s goop all over everything so it’s difficult to troubleshoot. The cord is in good shape (from previous experience, I’m now extra careful about straining it).

Has anybody worked on these before? Is there a part that fails frequently, or is there something I should check first? Power rails etc. Thanks.