HLA, Switchable HLA Inspection

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
Remove the plug hole plate. (See PLUG HOLE PLATE REMOVAL/INSTALLATION .)
Remove the ignition coil/ion sensors. (See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION .)
Remove the cylinder head cover. (See TIMING CHAIN REMOVAL/INSTALLATION .)

Press the rocker arm from above and verify that the HLA and switchable HLA does not drop.

If the HLA and switchable HLA drops, replace the HLA and switchable HLA. (See HYDRAULIC LASH ADJUSTER (HLA) REMOVAL/INSTALLATION .)

Courtesy of MAZDA MOTORS CORP.

Install in the reverse order of removal.