Normal Operation
WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
The engine temperature status is transmitted to the powertrain control module (PCM) from the cylinder head temperature sensor through circuit 8-RJ33 (WH/VT). The PCM transmits an over-temperature status to the instrument cluster over the communication network. When the engine temperature, as measured at the cylinder head, reaches 121° C (250° F), the PCM enters the first stage of the fail-safe mode and sends a command message to the instrument cluster to turn on the engine over-temperature warning indicator. Instrument cluster DTC U1073 is set if the instrument cluster fails to receive the engine temperature status from the PCM.