What is an indication of a possible problem with the power steering system?

Difficulty in turning the steering wheel is a clear indication of a possible problem with the power steering system. This difficulty can arise from several issues, such as low power steering fluid levels, air in the system, or a failing power steering pump. When any of these problems occur, the assistance provided by the power steering system diminishes, making it harder for the driver to turn the wheel, especially at low speeds.

This contrasts with other options. The self-centering of the steering wheel is a normal function of the steering system and indicates that the alignment and suspension are working correctly. Bald tires can signify a range of issues related to tire wear or suspension alignment but are not direct indicators of power steering problems. Flickering dashboard lights might point to electrical system issues or battery problems but do not typically correlate with the operation of the power steering system. Thus, the difficulty in turning the steering wheel specifically highlights a malfunction within the power steering assistance, making it the correct choice.