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

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Master cylinder disassembly/assembly
Caution
If the master cylinder body is damaged, replace the unit as a
component. When securing the master cylinder in a vise, tighten only the
flange of the master cylinder.
1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
Stop ...
Mazda 6 Owners Manual: Panel light control switch inspection
1. Connect the connector to the panel light control switch.
2. Connect the negative battery cable.
3. Measure the voltage at the panel light control switch using voltmeter.
When inspecting terminal B for continuity, disconnect the panel light
control switch connector.
4. If the value are ...