Make sure the adjuster is locked.
Mazda 6 Owners Manual: Warning Light and Brake Pad Wear Indicator
Warning Light
The warning light turns on when the system has a malfunction.
Refer to Warning Indication/Warning Lights
Brake Pad Wear Indicator
When the disc brake pads become worn, the built-in wear indicators contact the
disc plates. This causes a screeching noise to warn that the pads shoul ...
Mazda 6 Owners Manual: Foreword
Caution
When the engine does not start or stalls and the following DTCs
are not indicated, go to engine symptom troubleshooting.
Note
When the immobilizer system is defective, the engine cannot be
started.
If engine condition is normal but light stays on, inspect for
short circ ...