●Green : battery ok, i.e.: no water contained in the brake fluid

●Yellow : less than 1 % of water content in brake fluid

●Yellow / yellow : approximately 2 % of water content in brake fluid

●Yellow / yellow / red : approximately 3 % of water content in brake fluid

●The brake fluid should be changed

●Yellow / yellow / red / red : at least 4 % of water content in brake fluid

●The brake fluid must be changed urgently, extreme danger