Identify the problem
Check the owner’s manual
Inspect fluid levels
Check the battery
Inspect belts and hoses
Check fuses and relays
Scan for diagnostic trouble codes
Replace worn or damaged parts
Tighten loose connections
Test the brakes
Check tire pressure and condition
Inspect the engine air filter
Check the fuel system
Verify the starter and alternator
Test drive the car
Recheck for leaks, noises, or warning lights
Seek professional help if needed