Getting a "CHECK ENGINE" warning. Found code "PO520"; Engine oil pressure sensor circuit malfunction. The oil level and temperature is fine. Engine runs great, except when the Nanny kicks in, showing an oil icon, and goes into limp mode limiting RPM to 4000 and speed to about 53. Most of the time it simply shows check engine, showing an engine icon, but everything functions fine, RPM speed, etc. Bike is parked, of course, and looking for where this engine oil pressure sensor circuit is located to replace! Where is it?