Description And Operation: Overview

Due to the slower warm up times associated with the engine, an electric booster heater may be fitted to increase heater performance. The electric booster heater does this by heating the air leaving the heater assembly. The electric booster heater comprises ceramic coated thermistor elements. A request for electric booster heater operation originates in the Automatic Temperature Control Module (ATCM). This request is in the form of a relay energize signal to the Rear Junction Box (RJB) and the electric booster heater relays, integral with the RJB. This then provides power to the three sections of the electric booster heater, in accordance to the demand for heating.

The amount of heating requested by the ATCM is based on:

Ambient air temperature.
Engine coolant temperature.
Heating request.

NOTE: There is also a minimum blower-motor speed required for the electric booster heater operation.

The electric booster heater is limited to 600 Watts. If electrical load management is in force, electric booster heater performance will be reduced.