Auxiliary electric heater (Freelander 2)

Pos.	spare part no	Name
1	-	Heater assembly
2	-	Electric auxiliary heater

Since diesel engines warm up more slowly, an electric booster heater can be provided to increase the efficiency of the heater. The electric auxiliary heater heats the air leaving the heater unit.

The electric additional heater is equipped with ceramic-coated thermistor elements and a micro-controller. The request to turn on the electric auxiliary heater is generated in the automatic temperature control module (ATC). This request is sent to the central electrical box (CJB) over the medium speed CAN bus. CJB interprets this request and sends a PWM signal (pulse width modulation) to the micro-controller of the electric auxiliary heater. The duration of the pulses emitted from the CJB is proportional to the required heating intensity.

The intensity of heating requested by the ATC module depends on the following factors:

• Outside temperature
• Engine coolant temperature (ECT)
• Heating request

NOTE: The electric auxiliary heater also requires a minimum blower motor speed to operate.

The output of the electric auxiliary heater is limited to 1.25 kW. If electrical load control is active, the efficiency of the electric auxiliary heater is reduced.

NOTE: Vehicles equipped with an electric auxiliary heater and heated windshield use an upgraded 180 amp alternator. For more information, please refer to the chapter: Alternator - 2.2L Duratorq - Td4 (414-02 Generator and voltage regulator, Description and principle of operation).