Which type of equipment is specifically forbidden on passenger cars in Texas?

The presence of a bell, siren, or exhaust whistle on passenger cars is specifically forbidden in Texas because these types of equipment are typically associated with emergency vehicles. Allowing them on regular passenger vehicles could cause confusion and potentially lead to dangerous situations, as other drivers may misinterpret the sound as an indication that an emergency vehicle is approaching. This regulation is designed to maintain safety on the roads by ensuring that emergency vehicle signals remain distinct and that only authorized vehicles can use such warning devices.

In contrast, fog lights, GPS navigation systems, and rear windshield defrosters are permissible on passenger cars. Fog lights, for example, can improve visibility in adverse weather conditions, GPS systems aid in navigation, and rear windshield defrosters are essential for clear visibility during cold weather. These items enhance safety and convenience, aligning with regulations that support safe driving practices.