If you're experiencing a squealing noise in your Toyota Solara, it's often an indication of a worn or loose belt. Start by visually inspecting the belts for any signs of wear, cracking, or looseness. If you notice any issues, it may be necessary to tighten or replace the belt. Another potential cause could be a faulty pulley or tensioner. If the noise persists after inspecting and addressing the belts and pulleys, it's recommended to have a professional mechanic diagnose and repair the issue.