Brake Fluid Level Sensor Inspection

WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the brake fluid level sensor connector from the master cylinder.
Inspect for continuity according to fluid level between the brake fluid level sensor terminals.
World manufacturer identification "JM1"

Fig 1: Locating Brake Fluid Level Sensor Terminals - World Manufacturer Identification "JM1"
Courtesy of MAZDA MOTORS CORP.

World manufacturer identification "3MZ"

Fig 2: Locating Brake Fluid Level Sensor Terminals - World Manufacturer Identification "3MZ"
Courtesy of MAZDA MOTORS CORP.
- If not as indicated in the table, replace the reserve tank. (See MASTER CYLINDER REMOVAL/INSTALLATION .)
Fig 3: Brake Fluid Level Sensor Terminals Continuity Chart
Courtesy of MAZDA MOTORS CORP.