Keller said the driver was in the area of 4100 South and 2600 West in Taylorsville about 10:55 a.m. Sunday when he spotted a man walking along the road alone.
The motorist thought the man resembled Hyde, who had been missing since 4 p.m. Wednesday. The man pulled over and shouted out "Benjamin" to see if the man would respond, Keller said.
"Everybody in the valley was looking for Benjamin," Keller said.
When Hyde responded, the man, who asked to remain anonymous, called Unified police and stayed with him until officers arrived.
Keller said Hyde appeared to be in good health, but becomes confused when he's off his medication so it's likely police may never know where he's been the past four days or how he ended up in Taylorsville.
Keller said it appeared Hyde had been sleeping outdoors during his ordeal.