Fuel Fired Booster Heater (NAS Only)
The Fuel Fired Booster Heater (FFBH) has only the FFBH coolant pump operational. The operation is control from the Automatic Temperature Control Module (ATCM) through the Fuel Fired Booster Heater Control Module (FFBHCM).
The FFBH coolant pump is operated to control the flow of engine coolant through the heater core in the climate control assembly.