The temperature dependence of the thermoelectric power, S(T), and the electrical resistivity of the magnetically ordered CeRu2Ge2 (TN=8.55K and TC=7.40K) were measured for pressures p<16GPa in the temperature range 1.2K<300K. Long-range magnetic order is suppressed at pc≈7.8GPa. Pressure drives S(T) through a sequence of temperature dependences, ranging from a behavior characteristic for magnetically ordered heavy fermion compounds to a typical behavior of intermediate-valent systems. At intermediate pressures a large positive maximum develops above 10K in S(T). Its origin is attributed to the Kondo effect and its position is assumed to reflect the Kondo temperature TK. The pressure dependence of TK is discussed in a revised and extended (T,p) phase diagram of CeRu2Ge2.