Oil supply system of an automatic transmission or automated manual transmission in a powertrain

An oil supply system of an automatic transmission or an automated manual transmission in a power train, the oil supply system comprising:

• an oil pan;
• a pressure line for supplying elements of the transmission with pressurized oil;
• a pumping device for pumping oil from said oil pan into said pressure line at a supply pressure P0;
• as a starting element, a hydrodynamic converter forming a subsection of said pressure line;
• a retarder oil circuit with a hydrodynamic retarder;
• a heat exchanger and switching valves, including at least a first switching valve and a second switching valve, disposed to selectively switch said heat exchanger as a subsection into said pressure line or into said retarder oil circuit;
• and
• a temperature sensor disposed in a direction of flow between said pumping device and said heat exchanger, and configured to detect an oil temperature of the oil in said pressure line at a position between said heat exchanger and said pump, selectively when said heat exchanger is switched into said pressure line or when said heat exchanger is switched into said retarder oil circuit.