Heat Protection

During aggressive use, such as extended driving in deep sand, the AWD system may implement a heat protection mode to protect the AWD clutch from damage. The PCM performs calculations to determine the need for the heat protection mode. If the AWD system detects an overheat condition, it enters a locked mode. If the heat in the Rear Drive Unit (RDU) continues to rise once in the locked mode, the PCM disables the Active Torque Coupling (ATC). This condition may be indicated by an AWD OFF message in the message center. To resume normal operation, stop the vehicle in a safe location and turn the engine off for at least 10 minutes. After the engine is restarted and the AWD system has adequately cooled down, the AWD OFF message turns off and normal AWD operation returns. In the event the engine is not stopped, the AWD OFF message turns off when the system cools and normal operation returns.

In addition during excessive use or trailer towing on slippery surfaces the AWD system may implement a heat protection mode to protect the PTU from damage. Without PTU temperature sensors, the PCM performs calculations to determine the need for the heat protection mode. With a PTU temperature sensor, the PCM reads the PTU temperature to determine the need for the heat protection mode. The AWD system reduces commanded torque only to situation deemed critical for minimal function. Once the maximum temperature limit is reached, then FWD only is commanded and indicated by an AWD OFF message in the message center.