During PDI on chassis dash components, which monitor should be checked?

The correct choice is the backup monitor, as it is essential during a pre-delivery inspection (PDI) phase to ensure that safety features related to reversing the vehicle are functioning properly. The backup monitor provides visual feedback to the driver about any obstacles behind the vehicle, enhancing safety when maneuvering in reverse.

Checking the backup monitor can help identify any issues with the camera or display system, which are critical for preventing accidents when backing up. Ensuring this component works correctly is a crucial part of ensuring the overall safety and reliability of the vehicle before it reaches the customer.

While the other monitors, such as the fuel, battery, and navigation monitors, are certainly important for the operation and functionality of the vehicle, they do not have the same direct safety implications during the reversing process, making the backup monitor a priority during the PDI.