The engine room blowers are powered by a Circuit Breaker and SPST switch at the helm. All these parts are available on e-Bay or at West Marine or a local marine store. Match the 12 volt blower mounting style and CFM. The trim tabs are "Bennett", a great product with great support. It's a bullet proof design so you probably have an electrical problem. Contact them directly or get a local marine electrician. The engine room hatch has a CB and DPDT switch at the helm that drives an electric motor on a linear actuator. Look for a label on the unit and search on-line for the source or contact Tiara, they are great at helping out. Also request they e-mail you a manual for the boat while talking to customer service. Capt. George