Abstract: When a truck engine (12) is not running, an auxiliary coolant heater (32) can heat engine coolant and pump it through an occupant compartment heater (16). A coolant flow control system (10), including a valve assembly (84), associates the auxiliary heater (32) with both the occupant compartment heater (16) and engine (12) for selectively distributing heated coolant. When engine (12) has been running and is shut off, auxiliary heater (32) can be turned on and valve assembly (84) operated for occupant compartment heating while keeping the engine (12) warm. When the engine is cold, the auxiliary heater can be turned on and the valve assembly can be operated for engine pre-heating prior to starting.

Abstract: Automated motor vehicle battery voltage protection is provided by setting voltage trip points for increasing engine speed and for shedding selected electrical loads. The system is effected by programming a vehicle body computer which communicates with, and exerts control over, various vehicle system controllers over one or more controller area networks. The body computer is programmed to monitor battery voltage and initiates an increase in engine speed first, and if that fails to restore a minimum battery voltage level, begins shedding loads in a predetermined order.