Air Speed: Notes

WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The blower motor forces outside air into 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 operate in any switch position other than OFF, as long as the ignition switch is in the RUN position. When the ignition switch is ON, power from the underhood fuse block is delivered to the load side of the blower motor relay through the ignition 3 voltage circuit. Once energized, the load control switch inside the relay connects the HVAC control module to power through the battery positive voltage circuit. The blower motor and mode switches are located within the HVAC control module. The blower motor OFF input is connected in series at the HVAC control module by the off blower motor control circuit.

Power is provided to the blower motor from the instrument panel fuse block. Depending upon selected blower speeds, voltage is either supplied directly to the blower motor or voltage is varied by a series of in-line resistors. Power and ground are provided to the HVAC control module by the battery positive voltage, ignition 3-voltage circuit, ground circuits and splice pack.