1. Remove the interlock cable.
2. With the slider pin as shown in the figure, verify that the interlock cable moves freely.

Key interlock inspection
Selector lever inspectionMazda 6 Service Manual: Key reminder switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the key reminder switch connector.
4. Inspect for continuity between the key reminder switch terminals using an
ohmmeter.
If not as specified, replace the key reminder ...