The numerical or letter error codes that appear on vending machine displays indicate specific problems with the machine's operation, allowing service personnel to diagnose and repair them. Different models of machines display different codes, depending on the manufacturer. To identify a particular machine's error codes, consult the troubleshooting section of the machine's owner's manual, which is often available on the manufacturer's website.
Most vending machines show error codes on their LED or digital display when the door is open for refilling. Some codes also appear while the machine is on but failing to operate. Machines show both main and detailed errors pinpointing the location of the problem for troubleshooting. After fixing the issue, the service person clears the error display.
Coca-Cola vending machines produced by the Royal Vendors and the Sanden Vendo companies have four-letter error codes with abbreviated words indicating the problem. "CHAr" or "CHnG" indicates a problem with the coin changer or its connections, while "bUAL" is a problem with the bill validator. A detail level error code of "bJ" indicates a jam, while "bFUL" is a full cash box and "bILL" is a defective motor. "FriG" or "rFrG" appears for issues with the refrigeration system or temperature sensors, and "Chut" signals that the chute needs adjustment.