The 1984-1989 Bose Amplifier Relay is bolted to a dash brace under the passenger side dash panel accessible from underneath, next to the directional flasher. Failure of this relay is often associated with "popping" and "crackling" sounds in the speakers.
This is also the main Engine Cooling Fan Relay for 1984 Corvettes.
Learn more from the following Mid America Motorworks Knowledge Library article:
Corvette 1984-1996 C4 Bose Radio System Troubleshooting Tips
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