If your vehicle is showing recirculation button doesn't work or won't stay on, here are the most likely causes and the parts you'll need to fix each one.
Most modern vehicles automatically disable the recirculation feature when the windshield defroster is turned on. This is an intentional design to pull in fresh, dry outside air to prevent interior moisture buildup and window fogging.
The small electric motor that moves the recirculation door can strip its internal plastic gears or burn out. When the climate control module detects that the door isn't moving, it often flashes the button light and turns it off.
The physical button on the dashboard or the internal circuit board of the climate control module has worn out, preventing the command from registering when pressed.
Debris like leaves or rodent nests can jam the physical flap. Additionally, a recently replaced cabin air filter that was installed backwards or crushed can block the door's movement, causing the actuator to bind.
A blown fuse or damaged wiring can cut power to the actuator or the specific circuit within the HVAC module responsible for the recirculation function.