Which of the following is NOT typically checked during a routine engine maintenance?

During routine engine maintenance, various components and fluids are checked to ensure overall functionality and reliability of the vehicle. Usually, battery terminals condition, oil quality, and coolant concentration are crucial checks that directly relate to engine operation and performance.

The battery terminals are inspected for corrosion, tightness, and general condition because a poor battery connection can lead to starting issues and electrical problems. Oil quality is evaluated to ensure that it is clean and properly lubricating engine components, as dirty or degraded oil can lead to engine wear and failure. Coolant concentration is tested to confirm that the coolant is effective in regulating engine temperature, which is vital to prevent overheating.

On the other hand, while brake fluid level is essential for the braking system's performance, it is not typically part of standard engine maintenance checks. Brake fluid is more closely related to the braking system rather than the engine itself, which is why it is the choice that does not fit within routine engine maintenance tasks.