Thermador cooling fan error

For this dual oven/range, keep getting cooling fan error on the main oven. I have replaced that specific cooling fan as well as the relay board that feeds power to the cooling fan. Still errors. No error code. There are no sail switches or temp sensors that I can see from the parts list for this model. The cooling fan appears to work well during the oven cycle. Any thoughts? There is a “cross flow” fan in the middle back of the unit that does not engage during the oven cycle…not sure if it should or not. Any help appreciated!

The middle fan should be running with the cooling fan during oven operation, by your description I would say your middle fan (larger one) is faulty