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 InspectionFuel Draining Procedure
WARNING:
Fuel line spills and leakage from the pressurized fuel system are dangerous.
Fuel can ignite and cause serious injury or death and damage. To prevent this,
complete the following inspection with the engine stopped.
Fuel is very flammable liquid. If fuel spills or leaks ...
Fuel Pressure Sensor
Purpose/Function
Detects the fuel pressure in the fuel distributor as basic information for
mainly determining the fuel injection amount.
Detects the fuel pressure in the fuel distributor and inputs it to the PCM
as a fuel pressure signal.
Construction
Installed on ...
Service Publications
Service Publications
Factory-authorized Mazda service publications are available for owners who wish
to do some of their own maintenance and repair.
When requesting any of our publications through an Authorized Mazda Dealer, refer
to the chart below.
If they do not have what you need in stock ...