Normal Operation

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The PCM uses the Cylinder Head Temperature (CHT) sensor to measure the engine temperature. The Instrument Panel Cluster (IPC) receives the engine temperature data from the PCM over the High Speed Controller Area Network (HS-CAN) communication bus. The IPC monitors the engine temperature data received from the PCM and commands the temperature gauge indication with a corresponding movement of the pointer.

The non-hybrid and hybrid temperature gauges appear differently but essentially function the same. The non-hybrid gauge is an analog gauge with a needle that points to a specified area of the gauge depending on the data received from the PCM. The hybrid gauge is a digital display that appears as a thermometer. The fill color of the thermometer is blue when the temperature is between the cold and normal ranges. When the temperature indicates an overheating condition, the fill color turns to red.

If the engine temperature data is missing for 5 seconds or less or if the IPC receives invalid engine temperature data for 5 seconds or less, the IPC defaults the temperature gauge to the last setting, based upon the last known good temperature status message. If the IPC does not receive the engine temperature status message for more than 5 seconds, the IPC sets DTC U0100:00 in continuous memory and defaults the temperature gauge to cold (C). If the engine temperature data is deemed invalid by the IPC for 5 seconds or more, the IPC sets DTC U0401:68 and defaults the temperature gauge to cold (C).

NOTE: If DTC U0100:00 is set in the IPC , other observable symptoms may be an inoperative tachometer, speedometer or odometer.

This pinpoint test is intended to diagnose the following: