What does Nissan Teana P0 198 fault code mean?

P0 198 fault code: line voltage of engine oil temperature sensor is too low. Engine oil refers to lubricating oil specially used for internal combustion engines. Besides lubrication, it also has the functions of cleaning, rust prevention and cooling. The engine oil base oil currently used is composed of hydrocarbons, polyalphaolefins (PAO) and polyene (PIO), all of which are organic compounds composed only of carbon and hydrogen. Some advanced engine oils will contain less than 20% esters.