Heater Assembly (page 4 of 6)

AIR CONDITIONING

DESCRIPTION AND OPERATION

82-15

Blower
The blower is installed between the air inlets and the evaporator, and consists of two open hub, centrifugal fans 
powered by a single electric motor. Operation of the electric motor is controlled by the ATC ECU via an output stage 
(voltage amplifier) installed in the outlet of the RH fan.

To produce the seven blower speeds the ATC ECU outputs a stepped control voltage between 0 and 8 V to the output 
stage, which regulates a battery power feed from the passenger compartment fusebox to the blower. The control 
voltage changes, in 1 V steps, between 2 V (blower speed 1) and 8 V (blower speed 7). If the control voltage is less 
than 2 V the blower is off.

Blower Output Stage