This *sounds* like you have 12v permanent (yellow wire) wired to your accessory line and 12v switched (orange wire) connected to your permanent feed.

Which (I've heard) can happen on some models of car with ISO connectors, because these two wires are swapped in the connector.

Hey, Fox, if this turns out to be the source of the problem, please post that here so we can put it in the FAQ. The headlight dimmer thing is already in the FAQ...

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Tony Fabris