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: Gear Shift Indicator (GSI)
The Gear Shift Indicator (GSI) supports you to obtain optimum fuel economy and
smooth driving. It displays the selected gear position in the instrument cluster
as well as notifies the driver to change to the most suitable gear position corresponding
to the actual driving condition.
CAUTIO ...