In a vehicle, how many back turn signal lamps are mandated?

In Texas, as per the vehicle safety inspection regulations, a vehicle must be equipped with two back turn signal lamps. This requirement ensures that other drivers on the road can clearly see when a vehicle is signaling to turn or change lanes, which enhances safety by reducing the likelihood of accidents caused by miscommunication of intent on the roadway. The presence of two turn signal lamps provides better visibility from various angles and distances, making it more effective in alerting vehicles behind and beside the signaling vehicle.

Having only one turn signal lamp could create confusion or reduce the clarity of the signal being given to other drivers, which is why the standard calls for two functional lamps. Other options, such as one, three, or four, do not meet the regulatory requirements, and vehicles typically come equipped with two as a standard practice for safety compliance.