Substantial defects are those that affect a vehicle’s “use, value, or safety” and were not caused by you. They can include issues that negatively affect the engine, braking system, driveline, suspension, rear differential, turbocharger, axle system, cooling system, or SRS/airbag system. The lemon law also pertains to electrical problems and issues with the navigation system. This list can give you an idea of how to know if your car is a lemon, but our California lemon law lawyers can provide more insight into substantial defects.