If the whistle isolating cock is open and the Windscreen Wiper and Horn MCB is also open, what should the driver do?

When the whistle isolating cock is open and the Windscreen Wiper and Horn MCB (Miniature Circuit Breaker) is also open, the most appropriate course of action for the driver is to place the MCB in the closed position and then check the Front Light Wiper MCB.

This response is correct because it directly addresses the potential issue with the circuit by first attempting to restore power through resetting the MCB. Closing this circuit is an essential step, as it may resolve the problem immediately if there wasn't a significant underlying fault prompting the MCB to trip in the first place.

Furthermore, checking the Front Light Wiper MCB after reopening the Windscreen Wiper and Horn MCB ensures that all related functions are operational and can further narrow down any electrical faults. This methodical approach allows the driver to systematically assess the situation, ensuring that all systems are functioning properly and that there are no additional issues that require attention.

The other choices do not facilitate a practical or immediate troubleshooting process. Resetting the MCB without checking could overlook a potentially serious fault, simply checking the manual may delay addressing operational safety, and verifying the whistle’s operational status, while it’s useful, does not directly address the immediate issue of the non-functioning