New Guy

Hello! New to forum. Been lurking for answers here for a few weeks. I have a 98 Foreman 400 that has been a great machine, finally just had my first issue.
Fan stopped running, read some info on this issue, and it sounds like a common problem. Long story short I bought a new control unit, fan now runs, but only after the oil light comes on. That seems to be too late?? Last nite I ordered an oil sensor, hoping that fixes the issue.:)