I fixed mine as well by carefully resoldering the amp board , it solved 99% of my ACC problems , I love the fact that all these little parts can be taken apart and fixed . At the moment I am fixing a weeping aux water pump on the 300CE by replacing a 5 cent O-ring , any other car would have a sealed unit that couldn't be taken apart without self destructing , eg Ford or GM .

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Democracy dies in darkness, you have to kick at the darkness till it bleeds daylight