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 InspectionClimate Control Unit [Manual Air Conditioner]
Purpose
The climate control unit performs air conditioning according to the operation
by the users and the driving conditions of the vehicle.
Function
The climate control unit determines optimum air-conditioning based on the
input signals from each sensor and the control mo ...
Seat Belt Warning Light
Purpose
The seat belt warning light warns the driver that a seat belt is not fastened.
Function
The instrument cluster flashes/illuminates the seat belt warning light based
on the following CAN signals:
Vehicle speed signal sent from PCM
Driver/passenge ...
Engine Oil Pressure Warning Light
Purpose
The engine oil pressure warning light warns the driver that the engine oil
level is insufficient.
Function
When the instrument cluster receives the engine oil pressure warning light
request signal sent from the PCM via the CAN signal, it illuminates the engine
oi ...