Control Assembly: Description and Operation

The Rear Auxiliary Heater Module operates independently from the vehicle front heater except that both systems receive their hot water supply from the engine cooling system.
Battery voltage for the rear heater module relays is supplied by the RED (2) and BRN (50) wires at the convenience center. The battery junction blower supplies battery voltage from the convenience center through the RED (2) wire. The RR/HVAC Fuse supplies battery voltage to the convenience center through the BRN/WHT (650) wire.
A dash-mounted rear heater switch controls the temperature mode door relay through the DK GRN (949) wire. The temperature mode door relay operates the temperature mode door motor which regulates the air temperature. The dash switch also controls the three blower speeds.
Manually operated airflow direction vents are located at the air outlet openings.