One problem related to tail light switch has been reported for the 1999 Ford Ranger. The most recently reported issues are listed below.
Tail lights operate intermittently. While operating the vehicle on the road at night, this could pose a safety hazard. Other drivers have indicated to me that the tail lights were not working even though the headlights are on and the light switch is in the on position. Spot checks by me show that sometimes they are working and sometimes they are not. Search engine results indicate that this is a common problem with this vehicle.