Worried friends took to the streets on Sunday to pass out flyers and canvas downtown Los Angeles to spread the word and ask the public for help.
Thiede, a 29-year-old driver for Uber and Lyft, was last seen on Feb. 11. He had a Lyft fare that day, but it is unknown if that is connected to his disappearance.
His vehicle is a black 2014 Nissan Altima with CA plates 7CSD450.
They say his cell phone was last detected in a Pico Union neighborhood not far from where he lives, but it has since gone dead or been turned off. It was used to make a 911 hangup call the day after he was last seen.
The LAPD is now investigating as family and friends plead for the public's help.
"I've known Josh for a long time," friend Kevin Young said. "He's a solid, good-natured, well-put-together guy. Didn't seem like he was having any issues whatsoever. Didn't seem like anyone was giving him a hard time at all."