When a whistle is blowing continuously and the lever has been unsuccessful, which MCB should be checked?

When a whistle is blowing continuously and the lever has been unsuccessful, the most appropriate MCB to check is the Front Light Wiper MCB. This is because the front light wiper is typically responsible for ensuring that the visibility through the windshield is maintained during adverse weather conditions. If there is a malfunction in this system, it could be directly related to the whistle alarm sounding continuously, indicating a potential fault that needs to be addressed.

Continuously blowing whistles are often an indication of safety or operation alerts, so any component that directly impacts visibility or operation is critical to check first. The other MCBs, such as those for the windscreen wiper and horn, door system, or lighting control, while important in their respective functions, are less likely to be directly related to the issue indicated by the alarm in conjunction with the lever's performance. Thus, focusing on the Front Light Wiper MCB aligns with standard diagnostic practices in fault finding.