Brake Fluid Level Sensor Inspection

WARNING: This page is about a different car, the 2017 Mazda CX-9. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
Disconnect the brake fluid level sensor connector. (See MASTER CYLINDER REMOVAL/INSTALLATION .)
Verify that the continuity is as indicated in the table.

Fig 1: Brake Fluid Level Sensor Connector
Courtesy of MAZDA MOTORS CORP.
- If not as indicated in the table, replace the master cylinder component. (See MASTER CYLINDER REMOVAL/INSTALLATION .)

Fig 2: Brake Fluid Level Sensor Terminals Continuity Chart

Courtesy of MAZDA MOTORS CORP.