MN16 Engine: FC 2D9B Knock Sensor, Signal Is Stored in the DME. Certain areas of the US experience extremely cold climate conditions during the winter months, which can cause the Service Engine Soon lamp to illuminate while the engine temperature is increasing to full operating temperature. The following fault may be stored in the DME: ??FC 2D9B Knock Sensor, Signal CAUSE Unfavorable DME knock sensor diagnostic at outside ambient temperatures below -5° C
