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 InspectionHow to Use This Manual
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Illustrations complement the words of the manual to best explain how to enjoy
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Air Bag System Warning Light [Standard Deployment Control System]
Purpose
The air bag system warning light notifies the driver of a malfunction in
the SRS air bag system.
Function
If a malfunction occurs in the SRS air bag system, the air bag system warning
light illuminates or flashes.
Construction
LEDs (light-emitting d ...
Sae Standards
In accordance with new regulations, SAE (Society of Automotive Engineers)
standard names and abbreviations are now used in this manual. The table below
lists the names and abbreviations that have been used in Mazda manuals up to
now and their SAE equivalents.
...