No. 4 Air Intake Mode Does Not Change: Notes

WARNING: This page is about a different car, the 2004 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Description & Possible Cause Table - Air Intake Mode Does Not Change

Courtesy of MAZDA MOTORS CORP.

When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If there is a problem, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.
When checking intake motor drive signal, test it within 20 seconds after switching REC/FRESH mode. For that signal turns off after 20 seconds .