Thank you very much luis38 !!! It was the washing solenoid valve, the prewash and rinse works well. The inconvenience now that it is a 3-way, they are disassembled to be able to clean, but I see a problem when changing the coil, since the wash and rinse come out as a single body, the prewash has a separate body (what which is the coil). I do not think I can get original replacement of only those 2 .. I thought that I do not use prewash, can I change the connections and hoses for washing and prewashing or is it necessary to use all 3 for a wash and rinse without prewash?