I had initially thought your solenoid would be like an electrical contactor - a small amount of current to operate a large relay controlling a larger current. Your solenoid appears to use an electrical current to perform a mechanical function. They rarely fail. Do you have continuity across the coil? It's probably a twelve volt coli but you need to know how far the moving part must move. Is it possible it is only dirty preventing free movement? The center will frequently be removable and should slide freely.