2007 - 2008 Corvette: GM TechLink Article: Auto Volume Error
Some owners of a 2007-08 Corvette equipped with US8 Radio and U66 Speaker System may comment of an Auto Volume Error message displayed on the radio when the Auto Volume button is pressed. The concern may be intermittent and will occur when the button is pressed with the ignition in RAP or ACC mode. This is due to the Vehicle Speed Sensor (VSS) message not being sent to the radio in these specific ignition modes.
This is normal operation. The vehicle must have the engine running or be in Ignition On Engine Off mode for at least 2 to 5 seconds before the Auto Volume selections will appear. Replacing the radio or any other component will not correct this concern.
- Thanks to Dino Poulos
February 2008 - GM TechLink