If you own a 1969-1976 Corvette, you know that there are many items in the interior that need attention. By now, most of these cars have replacement interiors, but one item that is often overlooked is the C3 Corvette Heat/AC Control Panel. Although it appears to be a very complicated piece for the average hobbyist to rebuild, we’ve written out step-by-step instructions in our technical article 1968-1976 Corvette Heat/AC Control Panel Rebuild. Follow along and you’ll have the control unit rebuilt in no time.
If your unit doesn’t work at all, the article will also show you how to “set” the switches. Not only will your unit function, it will also look great inside your Corvette’s interior. You can expect a couple of hours to complete this procedure, including removing the unit from your Corvette’s console, which also requires removing the shift plate and the vacuum lines and cables from the heater/air condition unit.
This rebuild will also work for 1968 Corvettes, except they do not have any vacuum lines attached to the heater control unit.
To get started, remove the large cover and switch assembly on the left side. Be sure to put the 1/4-inch screws in a place where you will not lose them. You can reuse the compressor and lower blower switches if they are good. Check them by depressing the black plastic slide to see if the contact opens. If the contact does not open, you need to replace the switch.
Once you’ve removed both switches, it’s time to remove the vacuum switch on the left side. Some years, depending on options, will also have a 3-outlet vacuum switch on the right side. Remove them both if your Corvette has them. Once those are off, remove the blower switch in the middle of the control unit. The support bar in front that attaches both sides also needs to be removed. Then remove the four 1/4-inch screws that hold the sides to the face, then discard the old face.
Next, remove the plastic thumb wheels by using a set of pliers or dykes to cut off the retaining clip, then the wheels will slide out and you can discard them.
These are the parts you need to keep – and clean. When the parts are clean, it’s time to start reassembling. Read 1968-1976 Corvette Heat/AC Control Panel Rebuild for complete reassembly instructions.
No matter how bad your C3 Corvette’s heater control unit looks when you start the rebuild, it’ll look like new again when you’re done. This project is well worth the few hours it’ll take. For other great DIY projects, visit Zip’s corvettemagazine.com, your online source for Corvette technical articles and how-to’s.