Because a drop in pressure triggers the cooler bypass... they could have chosen to reverse the bypass and cool the oil, they obviously knew where the issue was and it wasnt the cooler.
so if the problem isn't the cooler, why not reverse the bypass? If the leak is in the no 1 input module its going to keep leaking regardless isn't it? Why risk overheating the engine inputs as well?
Not a 92 driver so just keen to understand.