To troubleshoot, you'll need to consult your owner's manual. It will contain a fuse box diagram showing which fuse(s) are related to the power systems that the cruise control draws from. Common suspects would be fuses for the power train or possibly a main power fuse.
Important Note: Before checking any fuses, make sure the ignition is OFF. Incorrectly handling fuses can be dangerous. If you're not comfortable working with your vehicle's electrical system, it's best to take it to a qualified mechanic.
