Method for operation of an apparatus, said apparatus being a vehicle and comprising: - an engine for driving movement means of the vehicle; - means for transmission of the movement generated by the engine; - a first electro-pump, said first electro-pump being an electro-pump for circulating a lubricating liquid of the engine and/or of the transmission means and comprising a rotor, which moves the lubricating liquid, and control electronics; - a tank for the lubricating liquid from where the first circulating electro-pump draws the lubricating liquid; - a first group of physical sensors coinciding with: a sensor for the rotation speed of the rotor of the first electro-pump, a sensor for the temperature of the control electronics for the first electro-pump, a measuring device for measuring the current intensity at the input of the first electro-pump, a measuring device for measuring the supply voltage of the first electro-pump; the apparatus does not have a measuring device for measuring the temperature of the lubrication liquid in the tank and comprises estimation means for estimating a temperature of the lubricating liquid inside the tank depending on the inputs obtained from at least the sensors of the first group; the method comprises the steps of: - transmitting to said estimation means the data detected by said first group of sensors; - determining via said estimation means the temperature of the lubricating liquid present in said tank depending on the inputs obtained from at least the sensors of the first group. - an engine for driving movement means of the vehicle; - means for transmission of the movement generated by the engine; - a first electro-pump, said first electro-pump being an electro-pump for circulating a lubricating liquid of the engine and/or of the transmission means and comprising a rotor, which moves the lubricating liquid, and control electronics; - a tank for the lubricating liquid from where the first circulating electro-pump draws the lubricating liquid; - a first group of physical sensors coinciding with: a sensor for the rotation speed of the rotor of the first electro-pump, a sensor for the temperature of the control electronics for the first electro-pump, a measuring device for measuring the current intensity at the input of the first electro-pump, a measuring device for measuring the supply voltage of the first electro-pump; the apparatus does not have a measuring device for measuring the temperature of the lubrication liquid in the tank and comprises estimation means for estimating a temperature of the lubricating liquid inside the tank depending on the inputs obtained from at least the sensors of the first group; the method comprises the steps of: - transmitting to said estimation means the data detected by said first group of sensors; - determining via said estimation means the temperature of the lubricating liquid present in said tank depending on the inputs obtained from at least the sensors of the first group. a sensor for the rotation speed of the rotor of the first electro-pump, a sensor for the temperature of the control electronics for the first electro-pump, a measuring device for measuring the current intensity at the input of the first electro-pump, a measuring device for measuring the supply voltage of the first electro-pump; the apparatus does not have a measuring device for measuring the temperature of the lubrication liquid in the tank and comprises estimation means for estimating a temperature of the lubricating liquid inside the tank depending on the inputs obtained from at least the sensors of the first group; the method comprises the steps of: - transmitting to said estimation means the data detected by said first group of sensors; - determining via said estimation means the temperature of the lubricating liquid present in said tank depending on the inputs obtained from at least the sensors of the first group. - transmitting to said estimation means the data detected by said first group of sensors; - determining via said estimation means the temperature of the lubricating liquid present in said tank depending on the inputs obtained from at least the sensors of the first group.