Abstract: A method for controlling a compressor of a motor vehicle air conditioner that is designed for variable power draw and is driveable by the vehicle drive. The power draw of the compressor is subject to an upper limit that is set variably as a function of the difference between the maximum drive torque that the vehicle drive can deliver and the drive torque that is required to drive the vehicle. During a vehicle acceleration maneuver, the air conditioning power of the air conditioner is reduced only to the degree required to reach the desired acceleration.

Abstract: A process for monitoring the coolant level in a cooling system, in particular in a motor vehicle in which the relative pressure and the temperature of the coolant are measured on the high-pressure side of the coolant circuit, using the measured pressure value. A temperature assigned to the pressure value is established on the basis of a coolant specific function (temperature=f (pressure)) and the undercooling of the coolant is then determined by subtracting the measured temperature from the assigned temperature, which undercooling is analyzed as a measure for the coolant level.