problems in aftermarket steering wheels are very common. A bad/weak aftermarket button wouldn't surprise me at all.
A bump is unlikely to make the relay close even if it is bad. If there is something loose inside the relay would be the only way that could do it.
The only other posibility I can think of is a screw or something got loose inside the top of the column itself.
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No good ever came from dark and spooky. Norville "Shaggy" RogersThe Ogre's Fiero Cave (It's also at the top of every forum page...)