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

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Dual proportioning valve inspection (without abs)
1. Connect the SSTs to the brake pipes as shown in the figure.
2. Bleed the air from the brake system.
3. Measure the fluid pressure of the master cylinder and the rear brake.
If not within the specification, replace the dual proportioning valve.
Fluid pressure
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Mazda 6 Owners Manual: Instrument cluster repair
Note
The needle of speedometer or tachometer may continue to rotate
clockwise until it indicates over maximum graduation. If a customer
complains of this concern, repair the needle position according to the
following steps.
1. Verify the concern.
2. Turn the ignition switch to LOC ...