Why would the horn on a 2000 ford explorer go off?

The horn on a 2000 Ford Explorer could go off due to several reasons, such as a stuck horn relay, a malfunctioning steering wheel switch, or a short circuit in the wiring. Additionally, moisture or corrosion in the electrical connections can cause the horn to activate unexpectedly. If the horn sounds continuously, it may indicate a problem with the vehicle's alarm system or an issue with the vehicle's electrical system. It's advisable to have the vehicle inspected by a qualified mechanic to diagnose and resolve the issue.