Running out of electric?

[mimjed 0]

Got cought out in a stupidly heavy downpour today and had to drive through some puddles that were higher than the kerb.

 

Car/engine was and is fine but then the stereo had a crackle then went quiet.

 

Started to work as normal again. Put full beam on and it goes really quiet again, headlights seem dim too.

 

Any ideas? Will it dry out? Or is the alternator fooked?

 

No batt light on.

[Majik 0]

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