During a PMCS, what does "fluid levels" refer to?

During a PMCS, which stands for Preventive Maintenance Checks and Services, "fluid levels" specifically refers to checking the essential fluids that keep a vehicle operating smoothly and safely. This includes the oil, coolant, and brake fluid levels.

Oil is crucial for lubrication, reducing friction in the engine, and preventing overheating. The coolant is vital for maintaining the engine temperature and preventing it from overheating. Brake fluid is necessary for the hydraulic brake system to function properly, ensuring that the vehicle can stop safely and reliably.

Monitoring these fluid levels is an integral part of routine vehicle maintenance, as proper levels help prevent mechanical failure and promote safe operation of the vehicle. Keeping these fluids at recommended levels is vital for the vehicle's performance and reliability, making this option the correct answer.