A universal microcontroller test system, which aims to determine the parameters of thermoelectric modules under various thermal loads, has been designed and realised using a novel test method. The test system has been designed according to a more simplified form of the present formula set, which has been made to accept minimum variables as the input in order to obtain more precise results. It measures all the parameters of a working thermoelectric module by measuring only the hot-side temperature, module operation voltage, current and thermal voltage values of the module. The new test system has been used to measure a standard thermoelectric module (Melcor CP 1.4-127-10L) in order to verify its performance. It has also been used to test the operation of an experimental medical apparatus, which is used to induce hypothermia (low body temperature) in the brains of rats using a thermoelectric module.