Radiator fan problems.

Hello.
I have a renault 19 adaguio diesel. The radiator fan does not work when heated. I have changed thermorers, and it remains the same. If I can do the fan relay, brown thread, to dough, it works perfectly.If Bridge Thermorestoresist, does nothing.
I think there must be an electronic circuit that is the one who activates the relay, but I do not know where it is located, because from thermorence two threads come out, white and yellow and the relay arrives red with the 12 volts and the other brown that when putting it in mass the fan works.
If someone can help me, I will be very grateful.
Greetings. Manuel Lopez.

Let's see Tejo45: You say that you bridge thermor resistance and the fan does not work. To what I answer: it is normal that it does not work if you do not plug the cables. Or what is the same: unplugs the cables of thermor resistance and without plugging them, july.
If, when the cables together, the fan works, it is almost clear that the thermor resistance is the guilty. What happens is that \ "I can make me the fact that you have changed it for another and the problem persists. Given this, I ask you, does the radiator have enough water?
Tell me and keep talking.
All the best

Thanks for answering.
I take out the connector from thermorers that are two cables, one yellow and one white. If the Puentuo does not work the fan. The fan works, if I make a bridge of the relay cable that is near the expansion deposit, because two cables arrive, one red with the 12 volts and another brown, which leads to mass, acion the relay and therefore the fan works. This cable is the one that I think will go to an electronic circuit that is the one that does not know where it is, because if of thermorers, two cables, yellow and white and the relay come out and the relay arrives, red and brown, where do the colors change.
I thank you again, and I hope your answer.
Greetings. Manuel Lopéz.

Let's see friend: For the symptoms you describe, I take out the following conclusion: the brown cable must close the feeding circuit of the relay and this (the relay) is excited, but the brown cable closes the circuit to dough through white wire, through the thermor resistance, yellow cable and mass.
Or, brown cable, yellow cable, thermor resistance, white wire and dough.
Where do the brown cable of the relay feeding circuit and the yellow or white cable of thermor resistance come together? I think it is through a connector that is possibly disconnected.
When you disconnect the two cables from thermor resistance and the joints, the fan should go into service, because what you are really feeding is the circuit of the relay, which in turn sends tension to the fan so that every time the joints should hear the typical clac, clac of excitement of the relay and consequently the entrance of the fan.
Come and the bull that is a monkey.
Greetings

Hello.
That is what I believed, but something fails.
I have measured the continuity between the brown cable and the yellow and is null, the white is of mass. That is why I thought there was an intermediate circuit. I will make a bridge between the yellow cable and the brown, to see what happens.
Well, there may be some cut cable or a bad connector.
Thank you for everything and I tell you.
Greetings. Manuel.