assembly in one piece or maybe post on this site in classifieds. Make sure you use a new gasket when you remove the casting. They also sometimes get gummed up inside. Take it off and touch 12 volts + & - to the AAC contacts once it's off the casting and see if it clicks. Then it may be as simple as cleaning the inside of the casting. I had 2 die on my 300, and 1 on my 240.