Note
1. Drive the vehicle at 30 km/h {19 mph} or more.
2. Press on the cruise control main switch (1).

3. Operate each of the cruise control switches.
4. Stop the vehicle and let it idle.
5. Turn and hold the RESUME/ACCEL switch on for at least 3 seconds (2).
The cruise set indicator light will illuminate for 3 seconds,
and then go off for at least 2 seconds.
Thus, the condition detection mode begins.
6. The condition detection mode is canceled by turning the ignition switch to LOCK position or turning off the cruise control main switch.
Condition Code List

Note
Inspection of Diagnostic Trouble Codes
Foreword
Dtc 37
Dtc 01Mazda 6 Service Manual: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
...
Mazda 6 Service Manual: C-pillar trim removal/installation
4SD
1. Remove the tire house trim.
2. Turn the seaming welt over.
3. Remove the cap using a fastener remover, and remove the bolt (with curtain
air bag system).
4. Disengage clips A and clip B using a fastener remover.
5. Pull the C-pillar trim forward, then disengage hook C from the body, ...