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 InspectionCar Navigation System
Outline
The car-navigation system displays point-of-origin and road guidance maps
via the audio unit display and provides guidance and information to the desired
point of destination.
NOTE:
For the car-navigation system operation, refer to the owner's manual.
...
Joint Shaft Removal/Installation [Mzr 2.0, Mzr 2.3 Disi Turbo, Mzr 2.5]
CAUTION:
Performing the following procedures without first removing the ABS wheel-speed
sensor may possibly cause an open circuit in the wiring harness if it is pulled
by mistake. Before performing the following procedures, remove the ABS wheel-speed
sensor connector (axle side) and ...
Temporary Spare Tire
Inspect the temporary spare tire at least
monthly to make sure it is properly
inflated and stored.
NOTE
The temporary spare tire condition
gradually deteriorates even if it has not
been used.
The temporary spare tire is easier to
handle because of its construction which
is lighter and small ...