Piston Slap: Fixing a Corvette’s total buzzkill
My 1978 Corvette makes a buzzing sound in the cabin when I turn on the lights. The headlight doors open, close, and light properly, so the electrical and vacuum system behind everything also seems to be fine. Help please!
There’s a short answer and a long answer here, so let’s get the obvious out of the way: disconnecting the power going to the buzzer module and resume enjoyment of the Corvette. Since the module “buzzes” for headlight, seat belt, and ignition key activity, disconnect the single wire (in the fusebox) that goes to the buzzer. This plug in question is on a single wire on the side of the buzzer, as seen here and here.
If that one wire doesn’t shut up the buzzer when you hit the lights, removing the buzzer (i.e. disconnecting everything) is your best choice. Odds are there are no downsides for most owners, provided you aren’t seeking NCRS certification for your Corvette. But what if you want the buzzer to work as the factory intended all those years ago?
Since the buzzer isn’t available new or as a reproduction (yet?), this video gives a good overview of what’s inside the little black box. Odds are removing the buzzer from the Corvette, opening up the box, and inspecting the circuit board, chip, etc. by someone trained in repairing vintage electronics will lead to the source of the problem rather quickly. With any luck, the problem is a bad solder/connection or a busted resistor—the universal stuff that’s easily found on the shelf at a restoration shop. The tiny chip on the circuit board might be harder to find, but inspecting its part number (and pasting it into an eBay/Amazon search) will unearth the truth.
And what if the box cannot be refurbished? Well … how about giving that quick and easy fix (disconnecting the buzzer) another chance?
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