I don't find anything on the Internet about that type of failure on the S2.
Nor have I heard of it on this forum.
The fact that you smelled overheated electronics, does not sound good.
I suggest you go ahead and see what Canon Support says about the failure.
They will likely give you an estimate price to fix the problem.
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The unit is approx 36 months old, minimal usage. It failed in the middle of use and had that electronic "burning" scent. The unit failed with the lens open and expanded to full zoom and when it shut down, it did not retract. I've tried replacing with fresh batteries, recharged existing ones, cleaned battery contacts with eraser, compressed air in battery compartment, but the unit just does not power up at all or makes any effort to fire up.
Any suggestions is greatly appreciated.
Thanks...

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