To troubleshoot, you should:
1. Consult your owner's manual: This is the first and most important step. The manual will show you the location of all fuse boxes (there are usually several) and a fuse diagram indicating what each fuse protects. Look for fuses related to the body control module (BCM) or other related systems.
2. Check all fuses: Systematically check every fuse in the relevant fuse boxes, looking for any that are blown (visually inspect the fuse element for a broken wire). Use a test light or multimeter to verify if there's continuity if you're unsure.
3. Identify the relevant relay(s): Besides fuses, some cruise control systems utilize relays. Your owner's manual might help you locate and check these.
4. Professional Diagnosis: If you've checked all fuses and relays and the cruise control still doesn't work, it's time to seek professional help from a mechanic or automotive electrician. They have the tools and expertise to diagnose more complex electrical problems. They can use a scan tool to check for any diagnostic trouble codes (DTCs) stored within the vehicle's computer system, which will pinpoint the faulty component.
Simply replacing fuses randomly is not recommended, as it could potentially damage other parts of the vehicle's electrical system.
