1984 Heater Blower

[Myran Coburn]

Greetings,

I have a 1984 coupe. When I got it out of storage this spring, the heater blower did not work on high. It works fine on low & medium. I have replaced the blower switch, the resistor & the relay, but it still does not work. If I power the fan directly from the battery, it blows on high with no problem. I have tested the voltage coming out of the resistor & found that it goes from 6 volts to 8 volts to 12 volts when switching from low to medium to high. It seems that the relay is where the problem might be but it is new and the connection seems OK. Can anyone offer any suggestions? Thank you!

Myran

[Jim T.]

Re: 1984 Heater Blower

Corvettes in the years before yours powered the high speed operation of the fan motor by a separate power line with its own inline fuse that changed under the hood and not at the fuse block. Don't know if the 84 had this or not. Will check out my 85's service manual. Take a look at your owners manual and see what you can find. If you don't have a owners manual or service manual for your car you can purchase them from Helm Inc. I can't remember if the NCRS has the C4 manuals in their book store yet.

[Myran Coburn]

Re: 1984 Heater Blower

Hi Jim,

Thank you for the info. I will look for an in-line fuse.

Myran

[Jim T.]

Re: 1984 Heater Blower

Looked in my 85 service manual and found this. When the blower speed switch is in Hi, the Blower Resisters are bypassed. Battery voltage is applied to the coil of the Blower Relay to energize the relay, when the relay is energized, battery voltage is applied directly to the Blower Motor. The motor will run at its fastest speed.