1. Disconnect the brake fluid level sensor connector from the master cylinder.
2. Inspect for continuity according to fluid level between the brake fluid level sensor terminals.

If not as indicated in the table, replace the reserve tank..

Brake Switch InspectionBreak-In Period
No special break-in is necessary, but a few precautions in the first 1,000 km
(600 miles) may add to the performance, economy, and life of your Mazda.
• Do not race the engine.
• Do not maintain one constant speed,
either slow or fast, for a long period of time.
• Do not drive constantl ...
Panel Light Control Indicator Alarm
Purpose
The panel light control indicator alarm notifies the driver that the panel
light brightness is either at maximum or minimum.
Function
If the panel light control switch is in the maximum rotation position right
or left when the TNS switch ON signal (TNS and headlight ...
Air Bag System Warning Alarm [Two Step Deployment Control System]
Purpose
The air bag system warning alarm notifies the driver that a malfunction occurred
in the air bag system instead of the air bag system warning light.
Function
If a malfunction occurs in the air bag system while the air bag system warning
light cannot illuminate, the a ...