Air Speed - Front Control

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The blower motor forces air to circulate within the vehicle's interior. The vehicle operator determines the blower motor's speed when the driver places the blower switch in one of the following positions:

Low
M1
M2
M3
High

The blower motor will only operate in any switch position other than OFF, as long as the ignition switch is in the RUN position. The blower motor and mode switches are located within the HVAC control module. Vehicles equipped with A/C, the blower motor OFF input is connected in series at the HVAC control module by the off blower motor control circuit.

Depending upon the selected speed, power is provided to the blower motor from either the left instrument panel fuse block or the underhood junction block. The junction block only provides power when the High blower switch position is selected. Power and ground are provided to the HVAC control module by the ignition 3 voltage and the ground circuits.