I am NOT familiar with either your car or your CC amplifier. So, why am I answering? It has been my experiences ( over 35 years ) that when stuff works wet, but fails dry, it can often be traced to a bad ground connection. The srcews which actually hold down the components of a system to the car frame get rusty or corroded over time and dry contact resistance goes up. Get it wet and resistance drops. So, I'd try unscrewing and then re-installing the physical electrical modules of the CC system. Also, check the condition of the heavy ground cable which runs between the engine itself and the auto frame. Check the condition of the negitive battery cable where it is screwed to the body / frame. When I remount electronic modules to a frame I use stainless steel screws.

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