XSARA 1 heating fan 1

I have a Citroën Xsara 1 and the heater fan only works on setting 4. I thought the problem was with the heating elements, but when I removed them and checked them with a multimeter, they were fine. I think it's the control unit. If anyone has had the same problem, I would appreciate it if you could tell me how you solved it.

The problem is in the heating command make a linges and look like the contacts this