Cooler does not start

Hello you love, After a long time of desperate and not helping looking I’m here now. The following, I have nn twingo c06, 1.2 16v, After finally the craft has found an end and everything was grouchy, we have now the next problem….The cooler no longer jumps:… Fan fan turns free, we pull the plug from the thermo sensor and start the box runs the cooler…. Plug back in does not go… Thermo sensor is changed..No change… We have invested so much annoying and time in the ball to fix all the mistakes and problems and now the cooler breaks the neck…Haare gray coloring we don’t need anymore…. After we have invested so much time now should not fail in the problem. Maybe one of you can continue to help.