The 26-year-old singer joined Corden for a drive in Los Angeles during the Late Late Show with James Corden segment, released Thursday.
Horan and Corden started by singing Horan's single "Slow Hands." The song appears on Horan's debut solo album, Flicker, released in 2017.
The former One Direction singer then shared his phobia of birds, specifically pigeons. Corden had Horan face his fears by having an animal handler place pigeons on Horan's body.
"I hate birds. Mostly pigeons," Horan said. "I think they're horrible. I don't like the fact that they're not scared of us until you get really close to them."
Horan and Corden performed "Nice to Meet Ya," the lead single from Horan's new album, Heartbreak Weather. The pair also sang One Direction's song "Steal My Girl" and Horan's song "Put a Little Love On Me."
Horan then agreed to take a lie detector test with Corden. When asked if he truly thinks One Direction will get back together, Horan said yes.
Horan and Corden ended by singing Horan's song "No Judgment," which appears on Heartbreak Weather.
Horan released Heartbreak Weather on Friday. He described the album as "a concept album about a breakup" on The Late Late Show with James Corden earlier this week, and added dates to his Nice to Meet Ya tour Thursday.