Network Message Chart - Module Network Input Messages: Overview
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Engine Coolant Temperature Data | PCM | This message contains raw value from the engine coolant temperature. |
| Ambient air temperature filtered | PCM | This message contains filtered value from the ambient air temperature sensor. |
Cabin Coolant Heater System Operation (PHEV if equipped)
The cabin coolant heater system provides warm coolant to the heater core to warm the passenger compartment whenever the front HVAC control module requests heat and the vehicle is in a driving mode, remote started, or doing Cabin Drive Conditioning. A SOBDMC / HPCM controlled cabin coolant heater warms the coolant. The cabin heater coolant diverter valve allows two modes: Either an isolated coolant loop with cabin coolant heater, heater core, and cabin heater coolant pump or a combined loop of those components along with the engine and other coolant components. A cabin heater coolant temperature sensor in the cabin heater system provides the PCM with coolant temperature information.