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 InspectionIgnition Switch
Push Button Start Positions
The system operates only when the key is
within operational range.
Each time the push button start is pressed,
the ignition switches in the order of off,
ACC, and ON. Pressing the push button
start again from ON switches the ignition
off.
NOTE
The engine ...
Neutral Switch Removal/Installation [G35 M R]
1. Remove the battery cover..
2. Disconnect the negative battery cable.
3. Remove the battery component. (ex: battery, battery tray and PCM component)(See
BATTERY REMOVAL/INSTALLATION [MZR 2.0, MZR 2.5].)
4. Remove the aerodynamic under cover No.2..
5. Drain the oil from the transaxle..
...
Taking Action
Take the appropriate action and verify that the warning light turns off.
KEY Warning Light
Take the appropriate action and verify that the warning light turns off.
...