I had this fault ' P2681 Engine Bypass Valve control circuit open'. On mine, it was a connector that had water inside it. The connector was located under the inlet manifold. My independent garage had to get an auto electrician out to diagnose. It was nothing to do with the bypass valve. The electrician sprayed the connector with water dispersant. The mechanic suspected the water pump was leaking but there was no sign of coolant loss or water on the inside of undertray. I decided not to have the pump replaced as it would have cost over £500. My fix cost £68 four weeks ago and had no issues with EML code fault since.