Take the appropriate action and verify that the warning light turns off.

Taking Action
Message Indicated on DisplayMazda 6 Owners 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.
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Mazda 6 Owners Manual: Front brake (disc) inspection
Brake Judder Repair Hint
Description
Brake judder concern has the following 3 characteristics:
Steering wheel vibration
Steering wheel vibrates in the direction of its rotation. This characteristic
is most noticeable when applying brakes at a vehicle speed of 100-140 km/h
{62.1-86.8 mph}.
F ...